@article{RodriguezRicoYepesetal.2015, author = {Rodriguez, H{\´e}ctor and Rico, Sergio and Yepes, Ana and Franco-Echevarr{\´i}a, Elsa and Antoraz, Sergio and Santamar{\´i}a, Ram{\´o}n I. and D{\´i}az, Margerita}, title = {The two kinases, AbrC1 and AbrC2, of the atypical two-component system AbrC are needed to regulate antibiotic production and differentiation in Streptomyces coelicolor}, series = {Frontiers in Microbiology}, volume = {6}, journal = {Frontiers in Microbiology}, number = {450}, doi = {10.3389/fmicb.2015.00450}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-143048}, year = {2015}, abstract = {Two-component systems (TCSs) are the most important sensing mechanisms in bacteria. In Streptomyces, TCSs-mediated responses to environmental stimuli are involved in the regulation of antibiotic production. This study examines the individual role of two histidine kinases (HKs), AbrC1 and AbrC2, which form part of an atypical TCS in Streptomyces coelicolor. gRT-PCR analysis of the expression of both kinases demonstrated that both are expressed at similar levels in NB and NMMP media. Single deletion of abrC1 elicited a significant increase in antibiotic production, while deletion of abrC2 did not have any clear effect. The origin of this phenotype, probably related to the differential phosphorylation ability of the two kinases, was also explored indirectly, analyzing the toxic phenotypes associated with high levels of phosphorylated RR. The higher the AbrC3 regulator phosphorylation rate, the greater the cell toxicity. For the first time, the present work shows in Streptomyces the combined involvement of two different HKs in the response of a regulator to environmental signals. Regarding the possible applications of this research, the fact that an abrC1 deletion mutant overproduces three of the S. coelicolor antibiotics makes this strain an excellent candidate as a host for the heterologous production of secondary metabolites.}, language = {en} } @article{LueckerathLapaSpahmannetal.2013, author = {L{\"u}ckerath, Katharina and Lapa, Constantin and Spahmann, Annika and J{\"o}rg, Gerhard and Samnick, Samuel and Rosenwald, Andreas and Einsele, Herrmann and Knop, Stefan and Buck, Andreas}, title = {Targeting Paraprotein Biosynthesis for Non-Invasive Characterization of Myeloma Biology}, doi = {10.1371/journal.pone.0084840}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-111319}, year = {2013}, abstract = {Purpose Multiple myeloma is a hematologic malignancy originating from clonal plasma cells. Despite effective therapies, outcomes are highly variable suggesting marked disease heterogeneity. The role of functional imaging for therapeutic management of myeloma, such as positron emission tomography with 2-deoxy-2-[18F]fluoro-D-glucose (18F-FDG-PET), remains to be determined. Although some studies already suggested a prognostic value of 18F-FDG-PET, more specific tracers addressing hallmarks of myeloma biology, e.g. paraprotein biosynthesis, are needed. This study evaluated the amino acid tracers L-methyl-[11C]-methionine (11C-MET) and [18F]-fluoroethyl-L-tyrosine (18F-Fet) for their potential to image myeloma and to characterize tumor heterogeneity. Experimental Design To study the utility of 11C-MET, 18F-Fet and 18F-FDG for myeloma imaging, time activity curves were compared in various human myeloma cell lines (INA-6, MM1.S, OPM-2) and correlated to cell-biological characteristics, such as marker gene expression and immunoglobulin levels. Likewise, patient-derived CD138+ plasma cells were characterized regarding uptake and biomedical features. Results Using myeloma cell lines and patient-derived CD138+ plasma cells, we found that the relative uptake of 11C-MET exceeds that of 18F-FDG 1.5- to 5-fold and that of 18F-Fet 7- to 20-fold. Importantly, 11C-MET uptake significantly differed between cell types associated with worse prognosis (e.g. t(4;14) in OPM-2 cells) and indolent ones and correlated with intracellular immunoglobulin light chain and cell surface CD138 and CXCR4 levels. Direct comparison of radiotracer uptake in primary samples further validated the superiority of 11C-MET. Conclusion These data suggest that 11C-MET might be a versatile biomarker for myeloma superior to routine functional imaging with 18F-FDG regarding diagnosis, risk stratification, prognosis and discrimination of tumor subtypes.}, language = {en} } @article{DashtiGrkovicAbdelmohsenetal.2014, author = {Dashti, Yousef and Grkovic, Tanja and Abdelmohsen, Usama Ramadan and Hentschel, Ute and Quinn, Ronald J.}, title = {Production of Induced Secondary Metabolites by a Co-Culture of Sponge-Associated Actinomycetes, Actinokineospora sp EG49 and Nocardiopsis sp RV163}, series = {MARINE DRUGS}, volume = {12}, journal = {MARINE DRUGS}, number = {5}, issn = {1660-3397}, doi = {10.3390/md12053046}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-116547}, pages = {3046-3059}, year = {2014}, abstract = {Two sponge-derived actinomycetes, Actinokineospora sp. EG49 and Nocardiopsis sp. RV163, were grown in co-culture and the presence of induced metabolites monitored by H-1 NMR. Ten known compounds, including angucycline, diketopiperazine and beta-carboline derivatives 1-10, were isolated from the EtOAc extracts of Actinokineospora sp. EG49 and Nocardiopsis sp. RV163. Co-cultivation of Actinokineospora sp. EG49 and Nocardiopsis sp. RV163 induced the biosynthesis of three natural products that were not detected in the single culture of either microorganism, namely N-(2-hydroxyphenyl)-acetamide (11), 1,6-dihydroxyphenazine (12) and 5a, 6,11a, 12-tetrahydro-5a, 11a-dimethyl[1,4]benzoxazino[3,2-b][1,4]benzoxazine (13a). When tested for biological activity against a range of bacteria and parasites, only the phenazine 12 was active against Bacillus sp. P25, Trypanosoma brucei and interestingly, against Actinokineospora sp. EG49. These findings highlight the co-cultivation approach as an effective strategy to access the bioactive secondary metabolites hidden in the genomes of marine actinomycetes.}, language = {en} } @article{KunzLabesWieseetal.2014, author = {Kunz, Anna Lena and Labes, Antje and Wiese, Jutta and Bruhn, Torsten and Bringmann, Gerhard and Imhoff, Johannes F.}, title = {Nature's Lab for Derivatization: New and Revised Structures of a Variety of Streptophenazines Produced by a Sponge-Derived Streptomyces Strain}, series = {Marine Drugs}, volume = {12}, journal = {Marine Drugs}, number = {4}, issn = {1660-3397}, doi = {10.3390/md12041699}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-116816}, pages = {1699-1714}, year = {2014}, abstract = {Eight streptophenazines (A-H) have been identified so far as products of Streptomyces strain HB202, which was isolated from the sponge Halichondria panicea from the Baltic Sea. The variation of bioactivities based on small structural changes initiated further studies on new derivatives. Three new streptophenazines (I-K) were identified after fermentation in the present study. In addition, revised molecular structures of streptophenazines C, D, F and H are proposed. Streptophenazines G and K exhibited moderate antibacterial activity against the facultative pathogenic bacterium Staphylococcus epidermidis and against Bacillus subtilis. All tested compounds (streptophenazines G, I-K) also showed moderate activities against PDE 4B.}, language = {en} } @article{KochCappelNockeretal.2013, author = {Koch, Oliver and Cappel, Daniel and Nocker, Monika and J{\"a}ger, Timo and Floh{\´e}, Leopold and Sotriffer, Christoph A. and Selzer, Paul M.}, title = {Molecular Dynamics Reveal Binding Mode of Glutathionylspermidine by Trypanothione Synthetase}, series = {PLoS ONE}, volume = {8}, journal = {PLoS ONE}, number = {2}, doi = {10.1371/journal.pone.0056788}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-131070}, pages = {e56788}, year = {2013}, abstract = {The trypanothione synthetase (TryS) catalyses the two-step biosynthesis of trypanothione from spermidine and glutathione and is an attractive new drug target for the development of trypanocidal and antileishmanial drugs, especially since the structural information of TryS from Leishmania major has become available. Unfortunately, the TryS structure was solved without any of the substrates and lacks loop regions that are mechanistically important. This contribution describes docking and molecular dynamics simulations that led to further insights into trypanothione biosynthesis and, in particular, explains the binding modes of substrates for the second catalytic step. The structural model essentially confirm previously proposed binding sites for glutathione, ATP and two \(Mg^{2+}\) ions, which appear identical for both catalytic steps. The analysis of an unsolved loop region near the proposed spermidine binding site revealed a new pocket that was demonstrated to bind glutathionylspermidine in an inverted orientation. For the second step of trypanothione synthesis glutathionylspermidine is bound in a way that preferentially allows \(N^1\)-glutathionylation of \(N^8\)-glutathionylspermidine, classifying \(N^8\)-glutathionylspermidine as the favoured substrate. By inhibitor docking, the binding site for \(N^8\)-glutathionylspermidine was characterised as druggable.}, language = {en} } @article{SchoenfelderMarincolaGeigeretal.2013, author = {Schoenfelder, Sonja M. K. and Marincola, Gabriella and Geiger, Tobias and Goerke, Christiane and Wolz, Christiane and Ziebuhr, Wilma}, title = {Methionine Biosynthesis in Staphylococcus aureus Is Tightly Controlled by a Hierarchical Network Involving an Initiator tRNA-Specific T-box Riboswitch}, series = {PLoS Pathogens}, volume = {9}, journal = {PLoS Pathogens}, number = {9}, doi = {10.1371/journal.ppat.1003606}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-130365}, pages = {e1003606}, year = {2013}, abstract = {Abstract In line with the key role of methionine in protein biosynthesis initiation and many cellular processes most microorganisms have evolved mechanisms to synthesize methionine de novo. Here we demonstrate that, in the bacterial pathogen Staphylococcus aureus, a rare combination of stringent response-controlled CodY activity, T-box riboswitch and mRNA decay mechanisms regulate the synthesis and stability of methionine biosynthesis metICFE-mdh mRNA. In contrast to other Bacillales which employ S-box riboswitches to control methionine biosynthesis, the S. aureus metICFE-mdh mRNA is preceded by a 5′-untranslated met leader RNA harboring a T-box riboswitch. Interestingly, this T-box riboswitch is revealed to specifically interact with uncharged initiator formylmethionyl-tRNA \((tRNA_i^{fMet})\)while binding of elongator \(tRNA^{Met}\) proved to be weak, suggesting a putative additional function of the system in translation initiation control. met leader RNA/metICFE-mdh operon expression is under the control of the repressor CodY which binds upstream of the met leader RNA promoter. As part of the metabolic emergency circuit of the stringent response, methionine depletion activates RelA-dependent (p)ppGpp alarmone synthesis, releasing CodY from its binding site and thereby activating the met leader promoter. Our data further suggest that subsequent steps in metICFE-mdh transcription are tightly controlled by the 5′ met leader-associated T-box riboswitch which mediates premature transcription termination when methionine is present. If methionine supply is limited, and hence \((tRNA_i^{fMet})\) becomes uncharged, full-length met leader/metICFE-mdh mRNA is transcribed which is rapidly degraded by nucleases involving RNase J2. Together, the data demonstrate that staphylococci have evolved special mechanisms to prevent the accumulation of excess methionine. We hypothesize that this strict control might reflect the limited metabolic capacities of staphylococci to reuse methionine as, other than Bacillus, staphylococci lack both the methionine salvage and polyamine synthesis pathways. Thus, methionine metabolism might represent a metabolic Achilles' heel making the pathway an interesting target for future anti-staphylococcal drug development. Author Summary Prokaryote metabolism is key for our understanding of bacterial virulence and pathogenesis and it is also an area with huge opportunity to identify novel targets for antibiotic drugs. Here, we have addressed the so far poorly characterized regulation of methionine biosynthesis in S. aureus. We demonstrate that methionine biosynthesis control in staphylococci significantly differs from that predicted for other Bacillales. Notably, involvement of a T-box instead of an S-box riboswitch separates staphylococci from other bacteria in the order. We provide, for the first time, direct experimental proof for an interaction of a methionyl-tRNA-specific T-box with its cognate tRNA, and the identification of initiator \((tRNA_i^{fMet})\) as the specific binding partner is an unexpected finding whose exact function in Staphylococcus metabolism remains to be established. The data further suggest that in staphylococci a range of regulatory elements are integrated to form a hierarchical network that elegantly limits costly (excess) methionine biosynthesis and, at the same time, reliably ensures production of the amino acid in a highly selective manner. Our findings open a perspective to exploit methionine biosynthesis and especially its T-box-mediated control as putative target(s) for the development of future anti-staphylococcal therapeutics.}, language = {en} } @article{HarrisonClausJiangetal.2013, author = {Harrison, Odile B. and Claus, Heike and Jiang, Ying and Bennett, Julia S. and Bratcher, Holly B. and Jolley, Keith A. and Corton, Craig and Care, Rory and Poolman, Jan T. and Zollinger, Wendell D. and Frasch, Carl E. and Stephens, David S. and Feavers, Ian and Frosch, Matthias and Parkhill, Julian and Vogel, Ulrich and Quail, Michael A. and Bentley, Stephen D. and Maiden, Martin C. J.}, title = {Description and Nomenclature of Neisseria meningitidis Capsule Locus}, series = {Emerging Infectious Diseases}, volume = {19}, journal = {Emerging Infectious Diseases}, number = {4}, doi = {10.3201/eid1904.111799}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-131703}, pages = {566-573}, year = {2013}, abstract = {Pathogenic Neisseria meningitidis isolates contain a polysaccharide capsule that is the main virulence determinant for this bacterium. Thirteen capsular polysaccharides have been described, and nuclear magnetic resonance spectroscopy has enabled determination of the structure of capsular polysaccharides responsible for serogroup specificity. Molecular mechanisms involved in N. meningitidis capsule biosynthesis have also been identified, and genes involved in this process and in cell surface translocation are clustered at a single chromosomal locus termed cps. The use of multiple names for some of the genes involved in capsule synthesis, combined with the need for rapid diagnosis of serogroups commonly associated with invasive meningococcal disease, prompted a requirement for a consistent approach to the nomenclature of capsule genes. In this report, a comprehensive description of all N. meningitidis serogroups is provided, along with a proposed nomenclature, which was presented at the 2012 XVIIIth International Pathogenic Neisseria Conference.}, language = {en} } @phdthesis{Beckert2002, author = {Beckert, Cornelia}, title = {Biosynthese, Akkumulation und Strukturen von Styrylpyronen in gametophytischen und sporophytischen Geweben von Equisetum}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-3454}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2002}, abstract = {Untersuchungen zur Akkumulation phenolischer Inhaltsstoffe von Equisetum an gametophytischen und unterirdisch wachsenden sporophytischen Geweben vervollst{\"a}ndigten den Kenntnisstand der phenolischen Inhaltsstoffe in dieser Gattung. In beiden Geweben konnten - wie in oberirdischen sporophytischen Geweben - Hydroxyzimts{\"a}urederivate nachgewiesen werden. Styrylpyrone und Protoflavonoide ersetzen hier die in oberirdischen sporophytischen Geweben nachgewiesenen Flavonoide. Hydroxyzimts{\"a}urederivate wurden in Prothallien aller untersuchter Arten gefunden wohingegen in Rhizomen der jeweiligen Arten einzelne Hydroxyzimts{\"a}urederivate fehlten. Die Inhaltsstoffmuster der Styrylpyrone bei verschiedenen Arten entsprachen sich weitgehend. Die sukzessive Analyse des {\"U}bergangsbereiches - unterirdisch wachsendes Rhizom zu oberirdischem Spross - zeigte einen ebenso sukzessiven Wechsel im Akkumulationsmuster. Der Gehalt l{\"o}slicher Styrylpyrone nahm - von unten nach oben betrachtet - in gleichem Maße ab, wie der Gehalt an Flavonoiden anstieg. In lokal braun pigmentierten Sprossbereichen, die vereinzelt an oberirdisch wachsenden Sporophyten auftraten, wurden neben den in Rhizomen konstitutiv akkumulierten Styrylpyronen auch, offenbar durch Verwundung induziert, Styrylpyrone detektiert. In den gr{\"u}nen, nicht pigmentierten Bereichen dieser Sprosse wurden dagegen ausschließlich Flavonoide und Hydroxyzimts{\"a}urederivate detektiert. Fluoreszenzmikroskopische Untersuchungen belegten eine vakuol{\"a}re Speicherung der l{\"o}slichen Inhaltsstoffe Styrylpyrone und Hydroxyzimts{\"a}urederivate in Rhizomen und Prothallien. Hydroxyzimts{\"a}urederivate wurden vorwiegend in zentral liegenden Rhizombereichen detektiert, w{\"a}hrend Styrylpyrone {\"u}ber den gesamten Rhizomquerschnitt verteilt sichtbar gemacht werden konnten. Folgende Styrylpyrone wurden aus Rhizomen von E. arvense isoliert und mit Hilfe spektroskopischer Methoden in ihrer Struktur aufgekl{\"a}rt: 3,4-Dihydroxy-6-(4´-hydroxy-E-styryl)-2-pyron-3-O-ß-D-glucopyranosid und 3,4-Dihydroxy-6-(3´-hydroxy-4´methoxy-E-styryl)-2-pyron-3-O-ß-glucopyranosid. Untersuchungen zur Biosynthese von Styrylpyronen zeigten eine enzymkatalysierte Bildung von Hispidin und Bisnoryangonin in Gametophyten verschiedener Equisetum-Arten sowie in Rhizomen und fertilen Sporophyten von E. arvense. Ebenso gelang der Nachweis der enzymatischen Glycosilierung von 3-Hydroxyhispidin zu Equisetumpyron in Gametophyten von E. arvense. Eine Styrylpyronsynthase wurde charakterisiert: Das pH-Optimum f{\"u}r die Bildung von Bisnoryangonin lag bei pH 7,5-7,8 und f{\"u}r die Bildung von Hispidin bei 6,8-7,0, jeweils in 0,5 M KPi-Puffer. Das Temperaturoptimum f{\"u}r die Bildung von Bisnoryangonin betrug 30° C bzw. 37°C f{\"u}r die Bildung von Hispidin. Die Substanzen Natriumascorbat in einer Konzentration von 20 mM, BSA (0,1 \% w/V), Dithiothreitol (2,5 mM) bzw. Mercaptoethanol (7 mM) konnten die Enzymaktivit{\"a}t deutlich steigern. Die Km\&\#64979;Werte wurden f{\"u}r die Substrate Kaffeoyl-CoA und Malonyl-CoA bei 116 µM bzw. 141 µM ermittelt. F{\"u}r die Substrate p-Cumaroyl-CoA und Malonyl-CoA lagen die Km\&\#64979;Werte bei 182 µM bzw. 238 µM. Das relative Molekulargewicht des nativen Enzyms wurde mittels Gelfiltration mit 78-80 kD bestimmt. Im Rahmen der Proteinreinigung wurde eine auf chromatographischen Techniken basierende Methode entwickelt, mit der die Styrylpyronsynthase mit einem Anreicherungsfaktor von 1107 bei einer Ausbeute von 0,08 \% gereinigt werden konnte.}, subject = {Schachtelhalm}, language = {de} } @phdthesis{Knauer2011, author = {Knauer, Michael}, title = {Aufkl{\"a}rung der Konstitution und Konfiguration von Sekund{\"a}rmetaboliten und Syntheseprodukten mittels NMR, MS, HPLC, CD und ORD sowie Beitr{\"a}ge zur Totalsynthese bioaktiver axial chiraler Naturstoffe}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-70990}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2011}, abstract = {Im Laufe der Evolution entwickelten Pflanzen, Bakterien, Pilze und Tiere eine Vielzahl von Signal-, Boten- und Abwehrstoffen. Diese f{\"u}r die Organismen oft lebensnotwendigen Sekund{\"a}rmetabolite werden von den jeweiligen Produzenten oft sehr effizient und teilweise auch hoch stereoselektiv produziert. Die Effizienz und Selektivit{\"a}t, mit denen diese Stoffe mit den in der Natur zur Verf{\"u}gung stehenden biosynthetischen Mitteln hergestellt werden, ist f{\"u}r Chemiker im Labor, trotz eines breiten Methodenrepertoires, eine große Herausforderung und oft gelingt die Laborsynthese nur {\"u}ber viele Stufen sowie in geringen Ausbeuten und/oder mit schlechten Enantio- oder Diastereoselektivit{\"a}ten. Daher wird in der chemischen Synthese immer wieder die Neuentwicklung und Erweiterung von Methoden vorangetrieben. Neben der Synthese im Labor ist auch die Untersuchung von Biosynthesewegen sowie die Charakterisierung der daf{\"u}r verantwortlichen Enzyme ein interessantes Forschungsgebiet, um von der Natur zu lernen und diese Erkenntnisse f{\"u}r die Entwicklung neuer Synthesestrategien und Methoden zu nutzen. Viele der bislang isolierten Verbindungen zeigen neben den f{\"u}r die produzierenden Organismen wichtigen Wirkungen auch Aktivit{\"a}ten gegen f{\"u}r Menschen gef{\"a}hrliche Krankheitserreger. Daher ist die Isolierung und Strukturaufkl{\"a}rung neuer bioaktiver Naturstoffe als Leitstrukturen f{\"u}r neue Medikamente ein lohnendes Ziel f{\"u}r Wissenschaftler. In den letzten Jahren wurden aber immer h{\"a}ufiger bereits bekannte Verbindungen isoliert. Zur Vermeidung solcher Mehrfachisolierung werden auch die analytischen Methoden zur Identifikation und Strukturaufkl{\"a}rung stetig verbessert Einen wichtigen Stellenwert hat hierbei die Kopplung von Messger{\"a}ten wie z.B. MS oder NMR mit chromatographischen Anlagen wie GC, HPLC oder UPLC eingenommen. Die Kombination von Fl{\"u}ssigchromatographie-Anlagen mit chiroptischen Detektoren wie CD-Spektrometern erlaubt hierbei manchmal sogar die Zuordnung von Absolutkonfigurationen direkt aus dem Rohextrakt. Ziel der vorliegenden Arbeit war einerseits die Anwendung neuer Methoden bei der Entwicklung von Syntheserouten zu axialchiralen Naturstoffen und andererseits die Aufkl{\"a}rung der Konstitution und Konfiguration von Naturstoffen und synthetischen Verbindungen sowie die Untersuchung von Biosyntheseintermediaten.}, subject = {Totalsynthese}, language = {de} } @phdthesis{Noll2006, author = {Noll, Torsten Frank}, title = {Aufkl{\"a}rung der Biosynthese und Faltungsmodi aromatischer Polyketide in pflanzlichen Gewebekulturen, Mikroorganismen und Insekten sowie Strukturaufkl{\"a}rung von entsprechenden Biosynthese-Intermediaten mittels HPLC-MS, NMR und CD}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-20187}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2006}, abstract = {Polyketide stellen aufgrund ihrer großen strukturellen Vielfalt nach wie vor Leit- und Wirkstoffe f{\"u}r die Pharma- und Pflanzenschutzforschung in den Industriel{\"a}ndern dar und bilden außerdem eine der wichtigsten Klassen von Naturstoffen (Sekund{\"a}rmetaboliten) {\"u}berhaupt. Besonders die Biosynthese aromatischer Polyketide und die hierbei involvierten Enzyme, die Polyketidsynthasen (PKS), wurden von Biosyntheseforschern als hervorragendes Modellsystem zur Untersuchung von Struktur-Funktions-Beziehungen von Multienzymkomplexen erkannt. F{\"u}r annelierte aromatische Polyketide existiert seit dem Jahr 2001 eine biosynthetische Klassifizierung auf Metabolitebene, das sogenannte Modus-F/S-System, mit dessen Hilfe man zwischen pro- und eukaryotischen Produzenten unterscheiden kann. Die Erforschung der detaillierten Biosynthese von aromatischen Polyketiden ist somit in mehrfacher Hinsicht ein lohnendes Ziel. In der vorliegenden Dissertation sollten die Biosynthese und die Faltungsmodi ausgew{\"a}hlter aromatischer Polyketide einschließlich der Charakterisierung potentieller Vorstufen in verschiedensten biologischen Systemen untersucht werden. Die dabei gewonnenen Resultate sind das Ergebnis interdisziplin{\"a}rer Zusammenarbeit.}, subject = {Polyketide}, language = {de} }