TY - JOUR
A1 - Gilmore, Michael S.
A1 - Cruz-Rodz, Armando L.
A1 - Leimeister-Wächter, Michaela
A1 - Kreft, Jürgen
A1 - Goebel, Werner
T1 - A Bacillus cereus cytolytic determinant, cereolysin AB, which comprises the phospholipase C and sphingomyelinase genes: nucleotide sequence and genetic linkage
N2 - A cloned cytolytic determinant from the genome of Bacillus cereus GP-4 has been characterized at the molecular Ievel. Nucleotide sequence determination revealed the presence of two open reading frames. 8oth open reading frames were found by deletion and complementation analysis to be necessary for expression of the hemolytic phenotype by Bacillus subtilis and Escherichia coli hosts. The 5' open reading frame was found to be nearly identical to a recently reported phospholipase C gene derived from a mutant B. cereus strain which overexpresses the respective protein, and it conferred a lecithinase-positive phenotype to the B. subtilis host. The 3' open reading frame encoded a sphingomyelinase. The two tandemly encoded activities, phospholipase C and sphingomyelinase, constitute a biologically functional cytolytic determinant of B. cereus termed cereolysin AB.
KW - Biologie
Y1 - 1989
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-60588
ER -
TY - JOUR
A1 - Brehm, Klaus
A1 - Haas, Albert
A1 - Goebel, Werner
A1 - Kreft, Jürgen
T1 - A gene encoding a superoxide dismutase of the facultative intracellular bacterium Listeria monocytogenes
N2 - A gene (Imsod) encoding superoxide dismutase (SOD; EC 1.15.1.1) of the facultative intracellular pathogen, Listeria monocytogenes, was cloned by functional complementation of an SOD-deficient Escherichia coli mutant. The nucleotide sequence was determined and the deduced amino acid (aa) sequence (202 aa) showed close similarity to manganese-containing SOD's from other organisms. Subunits of the recombinant L. monocytogenes SOD (re-SOD) and of both E. coli SODs formed enzymatically active hybrid enzymes in vivo. DNA/DNA-hybridization experiments showed that this type of recombinant re-sod gene is conserved within the genus Listeria.
KW - Biologie
Y1 - 1992
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-60515
ER -
TY - JOUR
A1 - Goebel, Werner
A1 - Kreft, Jürgen
T1 - Accumulation of replicative intermediates and catenated forms of the colicinogenic factor E\(_1\) in E. coli during the replication at elevated temperatures
N2 - No abstract available
KW - Biologie
Y1 - 1972
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-60625
ER -
TY - JOUR
A1 - Riedel, Alice
A1 - Mofolo, Boitumelo
A1 - Avota, Elita
A1 - Schneider-Schaulies, Sibylle
A1 - Meintjes, Ayton
A1 - Mulder, Nicola
A1 - Kneitz, Susanne
T1 - Accumulation of Splice Variants and Transcripts in Response to PI3K Inhibition in T Cells
N2 - Background: Measles virus (MV) causes T cell suppression by interference with phosphatidylinositol-3-kinase (PI3K) activation. We previously found that this interference affected the activity of splice regulatory proteins and a T cell inhibitory protein isoform was produced from an alternatively spliced pre-mRNA. Hypothesis: Differentially regulated and alternatively splice variant transcripts accumulating in response to PI3K abrogation in T cells potentially encode proteins involved in T cell silencing. Methods: To test this hypothesis at the cellular level, we performed a Human Exon 1.0 ST Array on RNAs isolated from T cells stimulated only or stimulated after PI3K inhibition. We developed a simple algorithm based on a splicing index to detect genes that undergo alternative splicing (AS) or are differentially regulated (RG) upon T cell suppression. Results: Applying our algorithm to the data, 9% of the genes were assigned as AS, while only 3% were attributed to RG. Though there are overlaps, AS and RG genes differed with regard to functional regulation, and were found to be enriched in different functional groups. AS genes targeted extracellular matrix (ECM)-receptor interaction and focal adhesion pathways, while RG genes were mainly enriched in cytokine-receptor interaction and Jak-STAT. When combined, AS/RG dependent alterations targeted pathways essential for T cell receptor signaling, cytoskeletal dynamics and cell cycle entry. Conclusions: PI3K abrogation interferes with key T cell activation processes through both differential expression and alternative splicing, which together actively contribute to T cell suppression.
KW - Biologie
Y1 - 2013
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-77917
ER -
TY - JOUR
A1 - Schmuck, R.
A1 - Kobelt, F.
A1 - Linsenmair, Karl Eduard
T1 - Adaptations of the reed frog Hyperbolius viridiflavus (Anura, Hyperbolidae) to its arid environment: V. Iridophores and nitrogen metabolism
N2 - Ofall amphibians living in arid habitats, reed frogs (belonging to the super species Hyperolius viridiflavus) are the most peculiar. Froglets are able to tolerate dry periods of up to 35 days or longer immediately after metamorphosis, in climatically exposed positions. They face similar problems to estivating juveniles, i.e. enduranee of long periods of high temperature and low RH with rather limited energy and water reserves. In addition, they must have had to develop meehanisms to prevent poisoning by nitrogenous wastes that rapidly accumulate during dry periods as a metabolie consequenee of maintaining a non-torpid state. During dry periods, plasma osmolarity of H. v. taeniatus froglets strongly increased, mainly through urea accumulation. Urea accumulation was also observed during metamorphic climax. During postmetamorphic growth, chromatophores develop with the density and morphology typical of the adult pigmentary pattern. The dermal iridophore layer, which is still incomplete at this time, is fully developed within 4-8 days after metamorphosis, irrespective of maintenance conditions. These iridophores mainly contain the purines guanine and hypoxanthine. The ability of these purines to reflect light provides an excellent basis for the role of iridophores in temperature regulation. In individuals experiencing dehydration stress, the initial rate of purine synthesis is doubled in eomparison to specimens continuously maintained under wet season conditions. This increase in synthesis rate leads to a rapid increase in the thiekness of the iridophore layer, thereby effectively reducing radiation absorption. Thus, the danger of overheating is diminished during periods of water shortage when evaporative cooling must be avoided. After the development of an iridophore layer of sufficient thickness for effective radiation reflectance, synthesis of iridophore pigments does not cease. Rather, this pathway is further used during the remaining dry season for solving osmotic problems eaused by accumulation of nitrogenous wastes. During prolonged water deprivation, in spite of reduced metabolic rates, purine pigments are produced at the same rate as in wet season conditions. This leads to a higher relative proportion of nitrogen end products being stored in skin pigments under dry season conditions. At the end of an experimental dry season lasting 35 days, up to 38% of the accrued nitrogen is stored in the form of osmotically inactive purines in thc skin. Thus the osmotic problems caused by evaporative water loss and urea production are greatly reduced.
KW - Biologie
KW - Zoologie
KW - Frosch
Y1 - 1988
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-78094
ER -
TY - JOUR
A1 - Linsenmair, Karl Eduard
A1 - Schmuck, R.
T1 - Adaptations of the reed frog Hyperbolius viridiflavus to its arid environment. III. Aspects of nitrogen metabolism and osmuregulation in the reed frog, H. viridiflavus taeniatus, with special reference to the role of iridophores
N2 - Reed frogs of the superspecies Hyperolius viridiflavus occur throughout the seasonally very dry and hot African savannas. Despite their small size (300-700 mg), estivating reed frogs do not avoid stressful conditions above ground by burrowing into the soil, but endure the inhospitable climate relatively unprotected, clinging to mostly dry grass sterns. They must have emcient mechanisms to enable them to survive e.g. very high temperatures, low relative hurnidities, and high solar radiation loads. Mechanisms must also have developed to prevent poisoning by the nitrogenous wastes that inevitably result from protein and nucleotide turnover. In contrast to fossorial amphibians, estivating reed frogs do not become torpid. Reduction in metabolism is therefore rather Iimited so that nitrogenous wastes accumulate faster in these frogs than in fossorial amphibians. This severely aggravates the osmotic problems caused by dehydration. During dry periods total plasma osmolarity greatly increases, mainly due to urea accumulation. Of the total urea accumulated over 42 days of experimental water deprivation, 30% was produced during the first 7 days. In the next 7 days rise in plasma urea content was negligible. This strong initial increase of urea is seen as a byproduct of elevated amino acid catabolism following the onset of dry conditions. Tbe rise in total plasma osmolarity due to urea accumulation, however, is not totally disadvantageous, but enables fast rehydration when water is available for very short periods only. Voiding of urine and feces eeases once evaporative water loss exceeds 10% of body weight. Tberefore, during continuous water deprivation, nitrogenous end products are not excreted. After 42 days of water deprivation, bladder fluid was substantially depleted, and urea coneentration in the remaining urine (up to 447 mM) was never greater than in plasma fluid. Feces voided at the end of the dry period after water uptake contained only small amounts of nitrogenous end products. DSF (dry season frogs) seemed not to be uricotelic. Instead, up to 35% of the total nitrogenous wastes produced over 42 days of water deprivation were deposited in an osmotically inert and nontoxic form in iridophore crystals. The increase in skin purine content averaged 150 µg/mg dry weight. If urea had been the only nitrogenous waste product during an estivation period of 42 days, lethal limits of total osmolarity (about 700 mOsm) would have been reached 10-14 days earlier. Thus iridophores are not only involved in colour change and in reducing heat load by radiation remission, but are also important in osmoregulation during dry periods. The seIective advantages of deposition of guanine rather than uric acid are discussed.
KW - Biologie
KW - Zoologie
KW - Frosch
KW - Hyperolius viridiflavus
KW - Estivation
KW - Osmoregulation
KW - Nitrogen metabolism
KW - lridophores
Y1 - 1988
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-78108
ER -
TY - JOUR
A1 - Linsenmair, Karl Eduard
T1 - Anemomenotactic orientation in beetles and scorpions
N2 - Scorpions, living in North African semideserts are - in spite of disrupting experimental interferences - able to maintain a certain direction in their natural environment in the dark on a plane surface. Under comparable laboratory conditions, excluding the possibility of light or gravity orientation, they can orient themselves if a directed air current passes over the "arena." In most cases the scorpions do not run necessarily with or against the wind, but rather maintain constant angles to the air current for anywhere from minutes to many hours. They are running anemomenotactically (ref. 1). Under identical conditions many species of beetles also orient themselves to air currents (refs. 2 to 4). The main problems to be solved in the study of anemomenotactic orientation are: (1) Which physical qualities of the air current have an influence on the anemomenotaxis? (2) With which sense organs do beetles and scorpions perceive wind directions? (3) Which physiological mechanism is the basis of anemomenotactic orientation? (4) What is the biological significance of anemomenotaxis in beetles and scorpions? With respect to these problems, more study has been done on beetles than on scorpions. Therefore, due to lack of space, I shall discuss mainly some of the results obtained in experiments with dung beetles (Geotrupes silvaticus, G. ,Stercorarius, G. armifrons, G. niger, Scarabaeus variolosus) and tenebrionid beetles (Tenebrio molitor, Pimelia grossa, P. tenuicomis, Scaurus dubius).
KW - Biologie
KW - Skorpion
KW - Käfer
Y1 - 1972
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-78118
ER -
TY - JOUR
A1 - Pimentel-Elardo, Sheila Marie
A1 - Kozytska, Svitlana
A1 - Bugni, Tim S.
A1 - Ireland, Chris M.
A1 - Moll, Heidrun
A1 - Hentschel, Ute
T1 - Anti-Parasitic Compounds from Streptomyces sp. Strains Isolated from Mediterranean Sponges
N2 - Actinomycetes are prolific producers of pharmacologically important compounds accounting for about 70% of the naturally derived antibiotics that are currently in clinical use. In this study, we report on the isolation of Streptomyces sp. strains from Mediterranean sponges, on their secondary metabolite production and on their screening for anti-infective activities. Bioassay-guided isolation and purification yielded three previously known compounds namely, cyclic depsipeptide valinomycin, indolocarbazole alkaloid staurosporine and butenolide. This is the first report of the isolation of valinomycin from a marine source. These compounds exhibited novel anti-parasitic activities specifically against Leishmania major (valinomycin IC50 < 0.11 μM; staurosporine IC50 5.30 μM) and Trypanosoma brucei brucei (valinomycin IC50 0.0032 μM; staurosporine IC50 0.022 μM; butenolide IC50 31.77 μM). These results underscore the potential of marine actinomycetes to produce bioactive compounds as well as the re-evaluation of previously known compounds for novel anti-infective activities.
KW - Biologie
KW - marine sponges
KW - Streptomyces
KW - valinomycin
KW - staurosporine
KW - butenolide
KW - anti-parasitic
Y1 - 2010
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-68312
ER -
TY - JOUR
A1 - Abdelmohsen, Usama Ramadan
A1 - Szesny, Matthias
A1 - Othman, Eman Maher
A1 - Schirmeister, Tanja
A1 - Grond, Stepanie
A1 - Stopper, Helga
A1 - Hentschel, Ute
T1 - Antioxidant and Anti-Protease Activities of Diazepinomicin from the Sponge-Associated Micromonospora Strain RV115
N2 - Diazepinomicin is a dibenzodiazepine alkaloid with an unusual structure among the known microbial metabolites discovered so far. Diazepinomicin was isolated from the marine sponge-associated strain Micromonospora sp. RV115 and was identified by spectroscopic analysis and by comparison to literature data. In addition to its interesting preclinical broad-spectrum antitumor potential, we report here new antioxidant and anti-protease activities for this compound. Using the ferric reducing antioxidant power (FRAP) assay, a strong antioxidant potential of diazepinomicin was demonstrated. Moreover, diazepinomicin showed a significant antioxidant and protective capacity from genomic damage induced by the reactive oxygen species hydrogen peroxide in human kidney (HK-2) and human promyelocytic (HL-60) cell lines. Additionally, diazepinomicin inhibited the proteases rhodesain and cathepsin L at an IC50 of 70–90 μM. It also showed antiparasitic activity against trypomastigote forms of Trypanosoma brucei with an IC50 of 13.5 μM. These results showed unprecedented antioxidant and anti-protease activities of diazepinomicin, thus further highlighting its potential as a future drug candidate.
KW - Biologie
KW - diazepinomicin
KW - anti-protease
KW - antioxidant
KW - actinomycetes
KW - Micromonospora
Y1 - 2012
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-76279
ER -
TY - JOUR
A1 - Goebel, Werner
A1 - Chakraborty, T.
A1 - Kreft, Jürgen
T1 - Bacterial hemolysins as virulence factors
N2 - No abstract available
KW - Biologie
Y1 - 1988
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-60553
ER -
TY - JOUR
A1 - Kramer, Michael D.
A1 - Binninger, Linda
A1 - Schirrmacher, Volker
A1 - Moll, Heidrun
A1 - Prester, Marlot
A1 - Nerz, Gaby
A1 - Simon, Markus M.
T1 - Characterization and isolation of a trypsin-like serine protease from a long-term culture cytolytic t cell line andits expression by functionally distinct T cells
N2 - No abstract available
KW - Biologie
Y1 - 1986
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-31636
ER -
TY - JOUR
A1 - Drechsler, Johannes
A1 - Grötzinger, Joachim
A1 - Hermanns, Heike M.
T1 - Characterization of the Rat Oncostatin M Receptor Complex Which Resembles the Human, but Differs from the Murine Cytokine Receptor
N2 - Evaluation of a pathophysiological role of the interleukin-6-type cytokine oncostatin M (OSM) for human diseases has been complicated by the fact that mouse models of diseases targeting either OSM or the OSM receptor (OSMR) complex cannot fully reflect the human situation. This is due to earlier findings that human OSM utilizes two receptor complexes, glycoprotein 130 (gp130)/leukemia inhibitory factor receptor (LIFR) (type I) and gp130/OSMR (type II), both with wide expression profiles. Murine OSM on the other hand only binds to the gp130/OSMR (type II) receptor complex with high affinity. Here, we characterize the receptor usage for rat OSM. Using different experimental approaches (knock-down of the OSMR expression by RNA interference, blocking of the LIFR by LIF-05, an antagonistic LIF variant and stably transfected Ba/F3 cells) we can clearly show that rat OSM surprisingly utilizes both, the type I and type II receptor complex, therefore mimicking the human situation. Furthermore, it displays cross-species activities and stimulates cells of human as well as murine origin. Its signaling capacities closely mimic those of human OSM in cell types of different origin in the way that strong activation of the Jak/STAT, the MAP kinase as well as the PI3K/Akt pathways can be observed. Therefore, rat disease models would allow evaluation of the relevance of OSM for human biology.
KW - Biologie
Y1 - 2012
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-78856
ER -
TY - JOUR
A1 - Kreft, Jürgen
A1 - Berger, Harald
A1 - Härtlein, Michael
A1 - Müller, Bodo
A1 - Weidinger, Gerhard
A1 - Goebel, Werner
T1 - Cloning and expression in Escherichia coli and Bacillus subtilis of the hemolysin (cereolysin) determinant from Bacillus cereus
N2 - From a cosmid gene bank of Bacillus cereus GP4 in Escherichia coli we isolated clones which, after several days of incubation, formed hemolysis zones on erythrocyte agar plates. These clones contained recombinant cosmids with B. cereus DNA insertions of varying lengths which shared some common restriction fragments. The smallest insertionwas recloned as aPstl fragment into pJKK3-1, a shuttle vector which repücates in Bacillus subtilis and E. coli. When this recombinant plasmid (pJKK3-1 hly-1) was transformed into E. coli, it caused hemolysis on erythrocyte agar plates, but in liquid assays no extemal or intemal hemolytic activity could be detected with the E. coli transformants. B. subtilis carrying the same plasmid exhibited hemolytic activity at Ievels comparable to those ofthe B. cereus donor strain. The hemolysin produced in B. subtilis seemed to be indistinguishable from cereolysin in its sensitivity to cholesterol, activation by dithiothreitol, and inactivation by antibodies raised against cereolysin. When the recombinant DNA carrying the cereolysin gene was used as a probe in hybridization experiments with chromosomal DNA from a streptolysin 0-producing strain of Streptococcus pyogenes or from üsteriolysin-producing strains of Usteria monoeytogenes, no positive hybridization signals were obtained. These data soggest that the genes for these three SH-activated cytolysins do not have extended sequence homology.
KW - Biologie
Y1 - 1983
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-60596
ER -
TY - JOUR
A1 - Haas, Albert
A1 - Brehm, Klaus
A1 - Kreft, Jürgen
A1 - Goebel, Werner
T1 - Cloning, characterization, and expression in Escherichia coli of a gene encoding Listeria seeligeri catalase, a bacterial enzyme highly homologous to mammalian catalases
N2 - A gene coding for catalase (hydrogen-peroxide:hydrogen-peroxide oxidoreductase; EC 1.11.1.6) of the grain-positive bacterium Listeria seeligeri was cloned from a plasmid library of EcoRI-digested chromosomal DNA, with Escherichia coli DHSa as a host. The recombinant catalase was expressed in E. coli to an enzymatic activity approximately SO times that of the combined E. coli catalases. The nucleutide sequence was determined, and the deduced amino acid sequence revealed 43.2% amino acid sequence identity between bovine liver catalase and L. seeligeri catalase. Most of the amino acid residues which are involved in catalytic activity, the formation of the active center accession channel, and heme binding in bovine liver catalase were also present in L. seeligeri catalase at the corresponding positions. The recombinant protein contained 488 amino acid residues and had a calculated molecular weight of 55,869. The predicted isoelectric point was 5.0. Enzymatic and genetic analyses showed that there is most probably a single catalase of this type in L. seeligeri. A perfect 21-bp inverted repeat, which was highly homologous to previously reported binding sequences of the Fur (ferric uptake regulon) protein of E. coli, was detected next to the putative promoter region of tbe L. seeligeri catalase gene.
KW - Biologie
Y1 - 1991
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-60536
ER -
TY - JOUR
A1 - Schartl, Manfred
A1 - Kneitz, Susanne
A1 - Wilde, Brigitta
A1 - Wagner, Toni
A1 - Henkel, Christiaan V.
A1 - Spaink, Hermann P.
A1 - Meierjohann, Svenja
T1 - Conserved expression signatures between medaka and human pigment cell tumors
N2 - Aberrations in gene expression are a hallmark of cancer cells. Differential tumor-specific transcript levels of single genes or whole sets of genes may be critical for the neoplastic phenotype and important for therapeutic considerations or useful as biomarkers. As an approach to filter out such relevant expression differences from the plethora of changes noted in global expression profiling studies, we searched for changes of gene expression levels that are conserved. Transcriptomes from massive parallel sequencing of different types of melanoma from medaka were generated and compared to microarray datasets from zebrafish and human melanoma. This revealed molecular conservation at various levels between fish models and human tumors providing a useful strategy for identifying expression signatures strongly associated with disease phenotypes and uncovering new melanoma molecules.
KW - Biologie
Y1 - 2012
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-75848
ER -
TY - JOUR
A1 - Albrecht, Marco
A1 - Sharma, Cynthia M.
A1 - Reinhardt, Richard
A1 - Vogel, Joerg
A1 - Rudel, Thomas
T1 - Deep sequencing-based discovery of the Chlamydia trachomatis transcriptome
N2 - Chlamydia trachomatis is an obligate intracellular pathogenic bacterium that has been refractory to genetic manipulations. Although the genomes of several strains have been sequenced, very little information is available on the gene structure of these bacteria. We used deep sequencing to define the transcriptome of purified elementary bodies (EB) and reticulate bodies (RB) of C. trachomatis L2b, respectively. Using an RNAseq approach, we have mapped 363 transcriptional start sites (TSS) of annotated genes. Semiquantitative analysis of mapped cDNA reads revealed differences in the RNA levels of 84 genes isolated from EB and RB, respectively. We have identified and in part confirmed 42 genome- and 1 plasmid-derived novel non-coding RNAs. The genome encoded non-coding RNA, ctrR0332 was one of the most abundantly and differentially expressed RNA in EB and RB, implying an important role in the developmental cycle of C. trachomatis. The detailed map of TSS in a thus far unprecedented resolution as a complement to the genome sequence will help to understand the organization, control and function of genes of this important pathogen.
KW - Biologie
Y1 - 2010
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-68389
ER -
TY - JOUR
A1 - Pimentel-Elardo, Sheila Marie
A1 - Grozdanov, Lubomir
A1 - Proksch, Sebastian
A1 - Hentschel, Ute
T1 - Diversity of Nonribosomal Peptide Synthetase Genes in the Microbial Metagenomes of Marine Sponges
N2 - Genomic mining revealed one major nonribosomal peptide synthetase (NRPS) phylogenetic cluster in 12 marine sponge species, one ascidian, an actinobacterial isolate and seawater. Phylogenetic analysis predicts its taxonomic affiliation to the actinomycetes and hydroxy-phenyl-glycine as a likely substrate. Additionally, a phylogenetically distinct NRPS gene cluster was discovered in the microbial metagenome of the sponge Aplysina aerophoba, which shows highest similarities to NRPS genes that were previously assigned, by ways of single cell genomics, to a Chloroflexi sponge symbiont. Genomic mining studies such as the one presented here for NRPS genes, contribute to on-going efforts to characterize the genomic potential of sponge-associated microbiota for secondary metabolite biosynthesis.
KW - Biologie
KW - nonribosomal peptide synthetase
KW - NRPS
KW - marine sponge
KW - Porifera
KW - metagenomics
Y1 - 2012
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-75990
ER -
TY - JOUR
A1 - Gründemann, Dirk
A1 - Gorboulev, Valentin
A1 - Gambaryan, Stepan
A1 - Veyhl, Maike
A1 - Koepsell, Hermann
T1 - Drug excretion mediated by a new prototype of polyspecific transporter
N2 - CATIO~IC drugs of different types and structures (antihistaminics, antiarrhythmics, sedatives, opiates, cytostatics and antibiotics, for example) are excreted in mammals by epithelial cells of the renal proximal tubules and by hepatocytes in the liver1-4. In the proximal tubules, two functionally disparate transport systems are involved which are localized in the basolateral and luminal plasma membrane and are different from the previously identified neuronal monoamine transporters and A TP-dependent multidrug exporting proteins1-3,5-12. Here we report the isolation of a complementary DNA from rat kidney that encodes a 556-amino-acid membrane protein, OCT1, which has the functional characteristics of organic cation uptake over the basolateral membrane of renal proximal tubules and of organic cation uptake into hepatocytes. OCTl is not homologous to any other known protein and is found in kidney, liver and intestine. As OCTl translocates hydrophobic and hydrophilic organic cations of different structures, it is considered to be a new prolotype of polyspecific transporters that are important for drug elimination.
KW - Biologie
Y1 - 1994
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-59327
ER -
TY - JOUR
A1 - Moll, Heidrun
T1 - Epidermal Langerhans cells are critical for immunoregulation of cutaneous leishmaniasis
N2 - In leishmaniasis, macrophages are known to play a central role as modulators of the specific immune activity. In this article, Heidrun Moll presents evidence for the critical involvement of another component of the skin immune system, the epidermal Langerhans cell. She proposes that Langerhans cells take up parasites in the skin and transport them to the draining lymph node for presentation to T cells and initiation of the specific immune response.
KW - Biologie
KW - Immunologie
Y1 - 1993
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-61323
ER -
TY - JOUR
A1 - Moll, Heidrun
A1 - Mitchell, Graham F.
A1 - McConville, Malcom J.
A1 - Handman, Emanuela
T1 - Evidence for T cell recognition in mice of a purified lipophosphoglycan from Leishmania major
N2 - We have previously reported that a Leishmania major lipophosphoglycan (LPG), given with killed Corynebacterium parvum as an adjuvant, can vaccinate mice against cutaneous leishmaniasis. In order to analyze whetber T cells are able to recognize this important parasite antigen, we have studied both humoral and cellular immune responses to L. major LPG that bad been isolated from promastigotes by sequential solvent extraction and bydrophobic chromatography. The data sbow that immunization of mice with highly purified LPG induced an increase in frequency of L. major-reactive T cells and the production of immunoglobulin G antibodies to LPG. Furthermore, genetically resistant mice infected with L. major were able to develop a specific delayed-type hypersensitivity response in the ear to L. major LPG. These findings strongly suggest that T cells can recognize and respond to glycolipid antigens, in this case a bost-protective Leishmania LPG, even though such antigens appear not to be potent T-cell stimulators in mice.
KW - Biologie
Y1 - 1989
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-61288
ER -
TY - JOUR
A1 - Kreft, Jürgen
A1 - Burger, Klaus J.
A1 - Goebel, Werner
T1 - Expression of antibiotic resistance genes from Escherichia coli in Bacillus subtilis
N2 - Bifunctional recombinant plasmids were constructed, comprised of the E. coli vectors pBR322, pBR325 and pACYC184 and different plasmids from Gram-positive bacteria, e.g. pBSU161-1 of B. subtilis and pUB110 and pC221 of S. aureus. The beta-lactamase (bla) gene and the chloramphenicol acetyltransferase (cat) gene from the E. coli plasmids were not transcribed and therefore not expressed in B. subtilis. However, tetracycline resistance from the E. coli plasmids was expressed in B. subtilis. Transcription of the tetracycline resistance gene(s) started in B. subtilis at or near the original E. coli promoter, the sequence of which is almost identical with the sequence recognized by σ55 of B. subtilis RNA polymerase.
KW - Biologie
Y1 - 1983
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-60600
ER -
TY - JOUR
A1 - Göb, Eva
A1 - Meyer-Natus, Elisabeth
A1 - Benavente, Ricardo
A1 - Alsheimer, Manfred
T1 - Expression of individual mammalian Sun1 isoforms depends on the cell type
N2 - Mammalian Sun1 belongs to an evolutionarily conserved family of inner nuclear membrane proteins, which are known as SUN domain proteins. SUN domain proteins interact with KASH domain partners to form bridging complexes, so-called LINC complexes, that physically connect the nuclear interior to the cytoskeleton. LINC complexes are critical for nuclear integrity and play fundamental roles in nuclear positioning, shaping and movement. The mammalian genome codes for at least five different SUN domain proteins used for the formation of a number of different LINC complexes. Recently, we reported on the identification of everal Sun1 isoforms, which tremendously enlarges the alternatives to form functional LINC complexes. We now confirmed that Sun1 actually exists in at least seven distinct splice variants. Besides that, we observed that expression of individual Sun1 isoforms remarkably depends on the cell type, suggesting a cell type-specific adaption of Sun1 dependent LINC complexes to specific cellular and physiological requirements.
KW - Biologie
KW - Sun1
KW - SUN domain protein
KW - LINC complex
KW - mouse
KW - nuclear envelope
KW - isoform
Y1 - 2011
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-68750
ER -
TY - JOUR
A1 - Moll, Heidrun
A1 - Müller, Christoph
A1 - Gillitzer, Reinhard
A1 - Fuchs, Harald
A1 - Röllinghoff, Martin
A1 - Simon, Markus M.
A1 - Kramer, Michael D.
T1 - Expression of T-cell-associated serine proteinase-1 during murine Leishmania major infection correlates with susceptibility to disease
N2 - The expression of T-cell-associated serine proteinase 1 (MTSP-1) in vivo during Leishmania major infection was analyzed in genetically resistant C57BL/6 mice and in genetically susceptible BALB/c mice. Using a monoclonal antibody as well as an RNA probe specific for MTSP-1 to stain tissue sections, we found T cells expressing MTSP-1 in skin lesions and spleens of mice of both strains. In skin lesions, MTSP-1-positive T cells could be detected as early as 3 days after infection. Most importantly, the frequency of T cells expressing MTSP-1 was significantly higher in susceptible BALB/c mice than in resistant C57BL/6 mice. These findings suggest that MTSP-1 is associated with disease-promoting T cells and that it may be an effector molecule involved in the pathogenesis of cutaneous leishmaniasis.
KW - Biologie
KW - Immunologie
Y1 - 1991
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-61311
ER -
TY - JOUR
A1 - Sturm, Julia B.
A1 - Hess, Michael
A1 - Weibel, Stephanie
A1 - Chen, Nanhei G.
A1 - Yu, Yong A.
A1 - Zhang, Quian
A1 - Donat, Ulrike
A1 - Reiss, Cora
A1 - Gambaryan, Stepan
A1 - Krohne, Georg
A1 - Stritzker, Jochen
A1 - Szalay, Aladar A.
T1 - Functional hyper-IL-6 from vaccinia virus-colonized tumors triggers platelet formation and helps to alleviate toxicity of mitomycin C enhanced virus therapy
N2 - Background: Combination of oncolytic vaccinia virus therapy with conventional chemotherapy has shown promise for tumor therapy. However, side effects of chemotherapy including thrombocytopenia, still remain problematic. Methods: Here, we describe a novel approach to optimize combination therapy of oncolytic virus and chemotherapy utilizing virus-encoding hyper-IL-6, GLV-1h90, to reduce chemotherapy-associated side effects. Results: We showed that the hyper-IL-6 cytokine was successfully produced by GLV-1h90 and was functional both in cell culture as well as in tumor-bearing animals, in which the cytokine-producing vaccinia virus strain was well tolerated. When combined with the chemotherapeutic mitomycin C, the anti-tumor effect of the oncolytic virotherapy was significantly enhanced. Moreover, hyper-IL-6 expression greatly reduced the time interval during which the mice suffered from chemotherapy-induced thrombocytopenia. Conclusion: Therefore, future clinical application would benefit from careful investigation of additional cytokine treatment to reduce chemotherapy-induced side effects.
KW - Biologie
KW - vaccinia virus
KW - cancer
KW - cytokine
KW - hyper-IL-6
KW - oncolysis
KW - chemotherapy
Y1 - 2012
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-75224
ER -
TY - JOUR
A1 - Goebel, Werner
A1 - Kathariou, S.
A1 - Kuhn, M.
A1 - Sokolovic, Z.
A1 - Kreft, Jürgen
A1 - Köhler, S.
A1 - Funke, D.
A1 - Chakraborty, T.
A1 - Leimeister-Wächter, M.
T1 - Hemolysin from Listeria-biochemistry, genetics and function in pathogenesis
N2 - No abstract available
KW - Biologie
Y1 - 1988
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-60563
ER -
TY - JOUR
A1 - Prusty, Bhupesh K.
A1 - Böhme, Linda
A1 - Bergmann, Birgit
A1 - Siegl, Christine
A1 - Krause, Eva
A1 - Mehlitz, Adrian
A1 - Rudel, Thomas
T1 - Imbalanced oxidative stress causes chlamydial persistence during non-productive Human Herpes Virus co-infection
N2 - Both human herpes viruses and Chlamydia are highly prevalent in the human population and are detected together in different human disorders. Here, we demonstrate that co-infection with human herpes virus 6 (HHV6) interferes with the developmental cycle of C. trachomatis and induces persistence. Induction of chlamydial persistence by HHV6 is independent of productive virus infection, but requires the interaction and uptake of the virus by the host cell. On the other hand, viral uptake is strongly promoted under co-infection conditions. Host cell glutathione reductase activity was suppressed by HHV6 causing NADPH accumulation, decreased formation of reduced glutathione and increased oxidative stress. Prevention of oxidative stress restored infectivity of Chlamydia after HHV6-induced persistence. We show that co-infection with Herpes simplex virus 1 or human Cytomegalovirus also induces chlamydial persistence by a similar mechanism suggesting that Chlamydia -human herpes virus co-infections are evolutionary shaped interactions with a thus far unrecognized broad significance.
KW - Biologie
Y1 - 2012
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-76215
ER -
TY - JOUR
A1 - Abdelmohsen, Usama Ramadan
A1 - Pimentel-Elardo, Sheila M.
A1 - Hanora, Amro
A1 - Radwan, Mona
A1 - Abou-El-Ela, Soad H.
A1 - Ahmed, Safwat
A1 - Hentschel, Ute
T1 - Isolation, Phylogenetic Analysis and Anti-infective Activity Screening of Marine Sponge-Associated Actinomycetes
N2 - Terrestrial actinomycetes are noteworthy producers of a multitude of antibiotics, however the marine representatives are much less studied in this regard. In this study, 90 actinomycetes were isolated from 11 different species of marine sponges that had been collected from offshore Ras Mohamed (Egypt) and from Rovinj (Croatia). Phylogenetic characterization of the isolates based on 16S rRNA gene sequencing supported their assignment to 18 different actinomycete genera representing seven different suborders. Fourteen putatively novel species were identified based on sequence similarity values below 98.2% to other strains in the NCBI database. A putative new genus related to Rubrobacter was isolated on M1 agar that had been amended with sponge extract, thus highlighting the need for innovative cultivation protocols. Testing for anti-infective activities was performed against clinically relevant, Gram-positive (Enterococcus faecalis, Staphylococcus aureus) and Gram-negative (Escherichia coli, Pseudomonas aeruginosa) bacteria, fungi (Candida albicans) and human parasites (Leishmania major, Trypanosoma brucei). Bioactivities against these pathogens were documented for 10 actinomycete isolates. These results show a high diversity of actinomycetes associated with marine sponges as well as highlight their potential to produce anti-infective agents.
KW - Biologie
KW - actinomycetes
KW - marine sponges
KW - anti-infective
KW - anti-parasitic
KW - phylogenetic
Y1 - 2010
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-68307
ER -
TY - JOUR
A1 - Moll, Heidrun
A1 - Scollay, Roland
T1 - L3T4+ T cells promoting susceptibility to murine cutaneous leishmaniasis express the surface marker Ly-24 (Pgp-1)
N2 - No abstract available
KW - Biologie
Y1 - 1989
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-61275
ER -
TY - JOUR
A1 - Haas, Albert
A1 - Dumbsky, Martina
A1 - Kreft, Jürgen
T1 - Listeriolysin genes: complete sequence of ilo from Listeria ivanovii and of lso from Listeria seeligeri
N2 - The completc DNA scqucnccs coding for thc thiol-activated cytolysins from Listeria ivanovii, ivanolysin 0 (ILO) and for sccligerolysin 0 (LSO) from Listeria seeligeri have been dctermined. Thc deduced amino acid scquences revealed that: (i) the primary translation products comprise 528 (ILO) and 530 (LSO) amino acids. respectively. (ii) ILO contains two cysteines. LSO has a substitution in the conserved cysteine motif.
KW - Biologie
KW - Thiol-activated cytolysin
KW - Listeriolysin O
KW - Cysteine: motif
KW - ( L. ivanovii )
KW - ( L. selligeri)
Y1 - 1992
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-60529
ER -
TY - JOUR
A1 - Menescal, Luciana
A1 - Schmidt, Cornelia
A1 - Liedtke, Daniel
A1 - Schartl, Manfred
T1 - Liver hyperplasia after tamoxifen induction of Myc in a transgenic medaka model
N2 - Myc is a global transcriptional regulator and one of the most frequently overexpressed oncoproteins in human tumors. It is well established that activation of Myc leads to enhanced cell proliferation but can also lead to increased apoptosis. The use of animal models expressing deregulated levels of Myc has helped to both elucidate its function in normal cells and give insight into how Myc initiates and maintains tumorigenesis. Analyses of the medaka (Oryzias latipes) genome uncovered the unexpected presence of two Myc gene copies in this teleost species. Comparison of these Myc versions to other vertebrate species revealed that one gene, myc17, differs by the loss of some conserved regulatory protein motifs present in all other known Myc genes. To investigate how such differences might affect the basic biological functions of Myc, we generated a tamoxifeninducible in vivo model utilizing a natural, fish-specific Myc gene. Using this model we show that, when activated, Myc17 leads to increased proliferation and to apoptosis in a dose-dependent manner, similar to human Myc. We have also shown that long-term Myc17 activation triggers liver hyperplasia in adult fish, allowing this newly established transgenic medaka model to be used to study the transition from hyperplasia to liver cancer and to identify Myc-induced tumorigenesis modifiers.
KW - Biologie
Y1 - 2012
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-75316
ER -
TY - JOUR
A1 - Schneider-Schaulies, Sibylle
A1 - Liebert, UG
A1 - Baczko, K.
A1 - ter Meulen, V.
T1 - Molecular Biological Aspects of Virus-Induced Subacute Encephalomyelitis in Lewis Rats
N2 - no abstract available
KW - Biologie
Y1 - 1988
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-81776
ER -
TY - JOUR
A1 - Ratzka, Carolin
A1 - Förster, Frank
A1 - Liang, Chunguang
A1 - Kupper, Maria
A1 - Dandekar, Thomas
A1 - Feldhaar, Heike
A1 - Gross, Roy
T1 - Molecular characterization of antimicrobial peptide genes of the carpenter ant Camponotus floridanus
N2 - The production of antimicrobial peptides (AMPs) is a major defense mechanism against pathogen infestation and of particular importance for insects relying exclusively on an innate immune system. Here, we report on the characterization of three AMPs from the carpenter ant Camponotus floridanus. Due to sequence similarities and amino acid composition these peptides can be classified into the cysteine-rich (e.g. defensin) and glycine-rich (e.g. hymenoptaecin) AMP groups, respectively. The gene and cDNA sequences of these AMPs were established and their expression was shown to be induced by microbial challenge. We characterized two different defensin genes. The defensin-2 gene has a single intron, whereas the defensin-1 gene has two introns. The deduced amino acid sequence of the C. floridanus defensins is very similar to other known ant defensins with the exception of a short C-terminal extension of defensin-1. The hymenoptaecin gene has a single intron and a very peculiar domain structure. The corresponding precursor protein consists of a signal- and a pro-sequence followed by a hymenoptaecin-like domain and six directly repeated hymenoptaecin domains. Each of the hymenoptaecin domains is flanked by an EAEP-spacer sequence and a RR-site known to be a proteolytic processing site. Thus, proteolytic processing of the multipeptide precursor may generate several mature AMPs leading to an amplification of the immune response. Bioinformatical analyses revealed the presence of hymenoptaecin genes with similar multipeptide precursor structure in genomes of other ant species suggesting an evolutionary conserved important role of this gene in ant immunity.
KW - Biologie
KW - Camponotus floridanus
Y1 - 2012
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-75985
ER -
TY - JOUR
A1 - Gorboulev, Valentin
A1 - Büchner, Hubert
A1 - Akhundova, Aida
A1 - Fahrenholz, Falk
T1 - Molecular cloning and functional characterization of V2 [8-Iysine] vasopressin and oxytocin receptors from a pig kidney cell line (LLC-PK1)
N2 - No abstract available
KW - Biologie
Y1 - 1993
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-59311
ER -
TY - JOUR
A1 - Gorboulev, Valentin
A1 - Akhundova, Aida
A1 - Büchner, Hubert
A1 - Fahrenholz, Falk
T1 - Molecular cloning of a new bombesin receptor subtype expressed in uterus during pregnancy
N2 - The homology screening approach has been used to clone a new member of the guanine-nucleotidebinding-protein-coupled receptor superfamily from guinea pig uterus. The cloned cDNA encodes a 399-amino-acid protein and shows the highest amino acid similarity to members of the bombesin receptor family; 52% and 47% similarity to the gastrin-releasing-peptide (GRP) receptor and the neuromedin-B receptor, respectively. Bindingexperiments with the stably transfected LLC-PK1 cell line expressing the new receptor protein confmned the bombesin-like nature of the cloned receptor. The relative order ofligand affinity, GRP = neuromedin C >> neuromedin B, suggests that the cloned cDNA represents the GRP subtype rather than the neuromedin-B subtype of bombesin receptors. Northern-blot analysis of mRNA species from several guinea-pig tissues showed that the mRNA for the new bombesin receptor subtype is expressed mainly in uteri of pregnant animals.
KW - Biologie
Y1 - 1992
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-59304
ER -
TY - JOUR
A1 - Gorboulev, Valentin
A1 - Akhundova, Aida
A1 - Luzius, Heike
A1 - Fahrenholz, Falk
T1 - Molecular cloning of substance P receptor cDNA from guinea-pig uterus
N2 - A cDNA encoding guinea-pig uterine substance P (SP) receptor has been isolated using the homology screening approach. Northern blot analysis reveals that the corresponding mRNA, of approx. 4.8 kb, is expressed in all tissues tested, but predominantly in the uteri of non-pregnant animals; during pregnancy its expression is reduced. The guinea-pig SP receptor was expressed in COS-7 cells and demonstrated relative Iigand affinity in the order: SP >> neurokinin A > neurokinin B.
KW - Biologie
KW - Substance P receptor
KW - G-protein-coupled receptor
KW - Guinea-pig uterus
KW - COS cell expression
Y1 - 1992
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-59293
ER -
TY - JOUR
A1 - Wehner, Nora
A1 - Weiste, Christoph
A1 - Dröge-Laser, Wolfgang
T1 - Molecular screening tools to study Arabidopsis transcription factors
N2 - In the model plant Arabidopsis thaliana, more than 2000 genes are estimated to encode transcription factors (TFs), which clearly emphasizes the importance of transcriptional control. Although genomic approaches have generated large TF open reading frame (ORF) collections, only a limited number of these genes is functionally characterized, yet. This review evaluates strategies and methods to identify TF functions. In particular, we focus on two recently developed TF screening platforms, which make use of publically available GATEWAY®-compatible ORF collections. (1) The Arabidopsis thaliana TF ORF over-Expression (AtTORF-Ex) library provides pooled collections of transgenic lines over-expressing HA-tagged TF genes, which are suited for screening approaches to define TF functions in stress defense and development. (2) A high-throughput microtiter plate based protoplast trans activation (PTA) system has been established to screen for TFs which are regulating a given promoter:Luciferase construct in planta.
KW - Biologie
KW - Arabidopsis thaliana
KW - transcription factor function
KW - screening tools
Y1 - 2011
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-69226
ER -
TY - JOUR
A1 - Pimentel-Elardo, Sheila M.
A1 - Buback, Verena
A1 - Gulder, Tobias A. M.
A1 - Bugni, Tim S.
A1 - Reppart, Jason
A1 - Bringmann, Gerhard
A1 - Ireland, Chris M.
A1 - Schirmeister, Tanja
A1 - Hentschel, Ute
T1 - New Tetromycin Derivatives with Anti-Trypanosomal and Protease Inhibitory Activities
N2 - Four new tetromycin derivatives, tetromycins 1–4 and a previously known one, tetromycin B (5) were isolated from Streptomyces axinellae Pol001T cultivated from the Mediterranean sponge Axinella polypoides. Structures were assigned using extensive 1D and 2D NMR spectroscopy as well as HRESIMS analysis. The compounds were tested for antiparasitic activities against Leishmania major and Trypanosoma brucei, and for protease inhibition against several cysteine proteases such as falcipain, rhodesain, cathepsin L, cathepsin B, and viral proteases SARS-CoV Mpro, and PLpro. The compounds showed antiparasitic activities against T. brucei and time-dependent inhibition of cathepsin L-like proteases with Ki values in the low micromolar range.
KW - Biologie
KW - tetromycin
KW - anti-trypanosomal
KW - protease inhibition
KW - Streptomyces axinellae
KW - marine sponge
Y1 - 2011
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-75465
ER -
TY - JOUR
A1 - Cornelius, C.
A1 - Leingärtner, A.
A1 - Hoiss, B.
A1 - Krauss, J.
A1 - Steffan-Dewenter, I.
A1 - Menzel, A.
T1 - Phenological response of grassland species to manipulative snowmelt and drought along an altitudinal gradient
N2 - Plant communities in the European Alps are assumed to be highly affected by climate change since temperature rise in this region is above the global average. It is predicted that higher temperatures will lead to advanced snowmelt dates and that the number of extreme weather events will increase. The aims of this study were to determine the impacts of extreme climatic events on flower phenology and to assess whether those impacts differed between lower and higher altitudes. In 2010 an experiment simulating advanced and delayed snowmelt as well as drought event was conducted along an altitudinal transect ca. every 250m (600-2000 m a.s.l.) in the Berchtesgaden National Park, Germany. The study showed that flower phenology is strongly affected by altitude; however there were few effects of the manipulative treatments on flowering. The effects of advanced snowmelt were significantly greater at higher than at lower sites, but no significant difference was found between both altitudinal bands for the other treatments. The response of flower phenology to temperature declined through the season and the length of flowering duration was not significantly influenced by treatments. The stronger effect of advanced snowmelt at higher altitudes might be a response to differences in treatment intensity across the gradient. Consequently, shifts in the date of snowmelt due to global warming may affect species more at higher than at lower altitudes since changes may be more pronounced at higher altitudes. Our data indicate a rather low risk of drought events on flowering phenology in the Bavarian Alps.
KW - Biologie
KW - Advanced snowmelt
KW - Alps
KW - BBCH
KW - Climate change
KW - Delayed snowmelt
KW - Flowering
Y1 - 2012
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-77969
N1 - ist zugleich: IV. Kapitel der Dissertation von Bernhard Hoiß
ER -
TY - JOUR
A1 - Schülein, Ralf
A1 - Kreft, Jürgen
A1 - Gonski, Sigrid
A1 - Goebel, Werner
T1 - Preprosubtilisin Carlsberg processing and secretion is blocked after deletion of amino acids 97-101 in the mature part of the enzyme
N2 - During an investigation into the substrate specificity and processing of subtilisin Carlsberg from Bacillus licheniformis, two major independent findings were made: (i) as has been shown previously, a stretch of five amino acids (residues 97-101 of the mature enzyme) that loops out into the binding cleft is involved in substrate binding by subtilisin Carlsberg. In order to see whether this loop element also determines substrate specificity, the coding region for these five amino acids was deleted from the cloned gene for subtilisin Carlsberg by site-directed mutagenesis. Unexpectedly the resulting mutant preproenzyme (P42c, Mr=42 kDa) was not processed to the mature form (Mr = 30 kDa) and was not released into the medium by a proteasedeficient B. subtilis host strain; rather, it accumulated in the cell membrane. This result demonstrates that the integrity of this loop element, which is very distant from the processing cleavage sites in the preproenzyme, is required for secretion of subtilisin Carlsberg. (ii) In culture supernatants from B. subtilis harbouring the cloned wild-type subtilisin Carlsberg gene the transient appearance (at 0-3 h after onset of stationary phase) of a processing intermediate (P38c, Mr = 38 kDa) oftbis protease could be demonstrated. P38c very probably represents a genuine proform of subtilisin Carlsberg.
KW - Biologie
KW - Bacillus
KW - Proenzyme
KW - Subtilisin maturation
KW - Site-directed mutagenesis
KW - Subtilisin Carlsberg
Y1 - 1991
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-60577
ER -
TY - JOUR
A1 - Kreft, Jürgen
A1 - Funke, Dorothee
A1 - Haas, Albert
A1 - Lottspeich, Friedrich
A1 - Goebel, Werner
T1 - Production, purification and characterization of hemolysins from Listeria ivanovii and Listeria monocytogenes Sv4b.
N2 - In culture supematants of both Listeria ivanovii and Listeria monocytogenes Sv4b, for the first time a hemolysin of molecular weight 58 kDa was identified, which had all the characteristics of an SH-activated cytolysin, and which was therefore identified as Iisteriolysin 0 (LLO). In the case of L. ivanovii a second major supematant protein of molecular weight 24 kDa co-purified with LLO. However, the function of this protein has to be determined. In culture supematants of L. ivanovii a sphingomyelinase and a Iecithinase activity could be detected, both enzymatic activities together contributing to the pronounced hemolysis caused by L. ivanovii. The N-tenninal amino acid sequences of LLO and the 24 kDa from L. ivanovii are shown.
KW - Biologie
KW - Hemolysin
KW - Listeria
Y1 - 1989
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-60545
ER -
TY - JOUR
A1 - Moll, Heidrun
A1 - Scollay, R.
A1 - Mitchell, G. F.
T1 - Resistance to cutaneous leishmaniasis in nude mice injected with L3T4+ T cells but not with Ly-2+ T cells
N2 - No abstract available
KW - Biologie
Y1 - 1988
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-61269
ER -
TY - JOUR
A1 - Moll, Heidrun
A1 - Röllinghoff, Martin
T1 - Resistance to murine cutaneous leishmaniasis is mediated by T\(_H\)1 cells, but disease-promoting CD4\(^+\) cells are different from T\(_H\)2 cells
N2 - No abstract available
KW - Biologie
KW - Immunologie
Y1 - 1990
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-61305
ER -
TY - JOUR
A1 - Beitzinger, Christoph
A1 - Stefani, Caroline
A1 - Kronhardt, Angelika
A1 - Rolando, Monica
A1 - Flatau, Gilles
A1 - Lemichez, Emanuel
A1 - Benz, Roland
T1 - Role of N-Terminal His6-Tags in Binding and Efficient Translocation of Polypeptides into Cells Using Anthrax Protective Antigen (PA)
N2 - It is of interest to define bacterial toxin biochemical properties to use them as molecular-syringe devices in order to deliver enzymatic activities into host cells. Binary toxins of the AB7/8-type are among the most potent and specialized bacterial protein toxins. The B subunits oligomerize to form a pore that binds with high affinity host cell receptors and the enzymatic A subunit. This allows the endocytosis of the complex and subsequent injection of the A subunit into the cytosol of the host cells. Here we report that the addition of an N-terminal His6-tag to different proteins increased their binding affinity to the protective antigen (PA) PA63-channels, irrespective if they are related (C2I) or unrelated (gpJ, EDIN) to the AB7/8-family of toxins. His6-EDIN exhibited voltage-dependent increase of the stability constant for binding by a factor of about 25 when the trans-side corresponding to the cell interior was set to 270 mV. Surprisingly, the C. botulinum toxin C2II-channel did not share this feature of PA63. Cell-based experiments demonstrated that addition of an N-terminal His6-tag promoted also intoxication of endothelial cells by C2I or EDIN via PA63. Our results revealed that addition of His6-tags to several factors increase their binding properties to PA63 and enhance the property to intoxicate cells.
KW - Biologie
Y1 - 2012
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-76325
ER -
TY - JOUR
A1 - Hsieh, Yu-Lung
A1 - Linsenmair, Karl Eduard
T1 - Seasonal dynamics of arboreal spider diversity in a temperate forest
N2 - Measuring and estimating biodiversity patterns is a fundamental task of the scientist working to support conservation and informmanagement decisions.Most biodiversity studies in temperate regions were often carried out over a very short period of time (e.g., a single season) and it is often—at least tacitly—assumed that these short-termfindings are representative of long-termgeneral patterns.However, should the studied biodiversity pattern in fact contain significant temporal dynamics, perhaps leading to contradictory conclusions. Here, we studied the seasonal diversity dynamics of arboreal spider communities dwelling in 216 European beeches (Fagus sylvatica L.) to assess the spider community composition in the following seasons: two cold seasons (I:November 2005–January 2006; II: February–April) and two warm seasons (III: May–July; IV: August–October). We show that the usually measured diversity of the warmseason community (IV: 58 estimated species) alone did not deliver a reliable image of the overall diversity present in these trees, and therefore, we recommend it should not be used for sampling protocols aimed at providing a full picture of a forest’s biodiversity in the temperate zones. In particular, when the additional samplings of other seasons (I, II, III) were included, the estimated species richness nearly doubled (108). Community I possessed the lowest diversity and evenness due to the harsh winter conditions: this community was comprised of one dominant species together with several species low in abundance. Similarity was lowest (38.6%) between seasonal communities I and III, indicating a significant species turnover due to recolonization, so that community III had the highest diversity. Finally, using nonparametric estimators, we found that further sampling in late winter (February–April) is most needed to complete our inventory. Our study clearly demonstrates that seasonal dynamics of communities should be taken into account when studying biodiversity patterns of spiders, and probably forest arthropods in general.
KW - Biologie
KW - Araneae
KW - canopy fogging
KW - European beech
KW - recolonization
KW - species richness estimation
KW - true diversity
Y1 - 2012
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-75158
ER -
TY - JOUR
A1 - Heisig, Julia
A1 - Weber, David
A1 - Englberger, Eva
A1 - Winkler, Anja
A1 - Kneitz, Susanne
A1 - Sung, Wing-Kin
A1 - Wolf, Elmar
A1 - Eilers, Martin
A1 - Wei, Chia-Lin
A1 - Gessler, Manfred
T1 - Target Gene Analysis by Microarrays and Chromatin Immunoprecipitation Identifies HEY Proteins as Highly Redundant bHLH Repressors
N2 - HEY bHLH transcription factors have been shown to regulate multiple key steps in cardiovascular development. They can be induced by activated NOTCH receptors, but other upstream stimuli mediated by TGFß and BMP receptors may elicit a similar response. While the basic and helix-loop-helix domains exhibit strong similarity, large parts of the proteins are still unique and may serve divergent functions. The striking overlap of cardiac defects in HEY2 and combined HEY1/HEYL knockout mice suggested that all three HEY genes fulfill overlapping function in target cells. We therefore sought to identify target genes for HEY proteins by microarray expression and ChIPseq analyses in HEK293 cells, cardiomyocytes, and murine hearts. HEY proteins were found to modulate expression of their target gene to a rather limited extent, but with striking functional interchangeability between HEY factors. Chromatin immunoprecipitation revealed a much greater number of potential binding sites that again largely overlap between HEY factors. Binding sites are clustered in the proximal promoter region especially of transcriptional regulators or developmental control genes. Multiple lines of evidence suggest that HEY proteins primarily act as direct transcriptional repressors, while gene activation seems to be due to secondary or indirect effects. Mutagenesis of putative DNA binding residues supports the notion of direct DNA binding. While class B E-box sequences (CACGYG) clearly represent preferred target sequences, there must be additional and more loosely defined modes of DNA binding since many of the target promoters that are efficiently bound by HEY proteins do not contain an Ebox motif. These data clearly establish the three HEY bHLH factors as highly redundant transcriptional repressors in vitro and in vivo, which explains the combinatorial action observed in different tissues with overlapping expression.
KW - Biologie
Y1 - 2012
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-75341
ER -
TY - JOUR
A1 - Koetschan, Christian
A1 - Foerster, Frank
A1 - Keller, Alexander
A1 - Schleicher, Tina
A1 - Ruderisch, Benjamin
A1 - Schwarz, Roland
A1 - Mueller, Tobias
A1 - Wolf, Matthias
A1 - Schultz, Joerg
T1 - The ITS2 Database III-sequences and structures for phylogeny
N2 - The internal transcribed spacer 2 (ITS2) is a widely used phylogenetic marker. In the past, it has mainly been used for species level classifications. Nowadays, a wider applicability becomes apparent. Here, the conserved structure of the RNA molecule plays a vital role. We have developed the ITS2 Database (http://its2.bioapps .biozentrum.uni-wuerzburg.de) which holds information about sequence, structure and taxonomic classification of all ITS2 in GenBank. In the new version, we use Hidden Markov models (HMMs) for the identification and delineation of the ITS2 resulting in a major redesign of the annotation pipeline. This allowed the identification of more than 160 000 correct full ength and more than 50 000 partial structures. In the web interface, these can now be searched with a modified BLAST considering both sequence and structure, enabling rapid taxon sampling. Novel sequences can be annotated using the HMM based approach and modelled according to multiple template structures. Sequences can be searched for known and newly identified motifs. Together, the database and the web server build an exhaustive resource for ITS2 based phylogenetic analyses.
KW - Biologie
Y1 - 2010
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-68390
ER -
TY - JOUR
A1 - Hoppe, J.
A1 - Sebald, Walter
T1 - The proton conducting F0-part of bacterial ATP synthases
N2 - No abstract available
KW - Biologie
Y1 - 1984
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-82019
ER -
TY - JOUR
A1 - Lampidis, Robert
A1 - Gross, Roy
A1 - Sokolovic, Zeljka
A1 - Goebel, Werner
A1 - Kreft, Jürgen
T1 - The virulence regulator protein of Listeria ivanovii is highly homologous to PrfA from Listeria monocytogenes and both belong to the Crp-Fnr family of transcription regulators
N2 - No abstract available
KW - Biologie
Y1 - 1994
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-60503
ER -
TY - JOUR
A1 - Härtlein, Michael
A1 - Schiessl, Sigrid
A1 - Wagner, Wilma
A1 - Rdest, Ursula
A1 - Kreft, Jürgen
A1 - Goebel, Werner
T1 - Transport of hemolysin by Escherichia coli
N2 - No abstract available
KW - Biologie
KW - Hemolysin
KW - Escberichia coli
KW - Gene cloning
KW - Expression
KW - Transport
Y1 - 1983
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-60619
ER -
TY - JOUR
A1 - Heddergott, Nico
A1 - Krüger, Timothy
A1 - Babu, Sujin B.
A1 - Wei, Ai
A1 - Stellamanns, Erik
A1 - Uppaluri, Sravanti
A1 - Pfohl, Thomas
A1 - Stark, Holger
A1 - Engstler, Markus
T1 - Trypanosome Motion Represents an Adaptation to the Crowded Environment ofthe Vertebrate Bloodstream
N2 - Blood is a remarkable habitat: it is highly viscous, contains a dense packaging of cells and perpetually flows at velocities varying over three orders of magnitude. Only few pathogens endure the harsh physical conditions within the vertebrate bloodstream and prosper despite being constantly attacked by host antibodies. African trypanosomes are strictly extracellular blood parasites, which evade the immune response through a system of antigenic variation and incessant motility. How the flagellates actually swim in blood remains to be elucidated. Here, we show that the mode and dynamics of trypanosome locomotion are a trait of life within a crowded environment. Using high-speed fluorescence microscopy and ordered micro-pillar arrays we show that the parasites mode of motility is adapted to the density of cells in blood. Trypanosomes are pulled forward by the planar beat of the single flagellum. Hydrodynamic flow across the asymmetrically shaped cell body translates into its rotational movement. Importantly, the presence of particles with the shape, size and spacing of blood cells is required and sufficient for trypanosomes to reach maximum forward velocity. If the density of obstacles, however, is further increased to resemble collagen networks or tissue spaces, the parasites reverse their flagellar beat and consequently swim backwards, in this way avoiding getting trapped. In the absence of obstacles, this flagellar beat reversal occurs randomly resulting in irregular waveforms and apparent cell tumbling. Thus, the swimming behavior of trypanosomes is a surprising example of micro-adaptation to life at low Reynolds numbers. For a precise physical interpretation, we compare our high-resolution microscopic data to results from a simulation technique that combines the method of multi-particle collision dynamics with a triangulated surface model. The simulation produces a rotating cell body and a helical swimming path, providing a functioning simulation method for a microorganism with a complex swimming strategy
KW - Biologie
Y1 - 2012
U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-78421
ER -