TY - JOUR A1 - Kohlmorgen, Britta A1 - Elias, Johannes A1 - Schoen, Christoph T1 - Improved performance of the artus Mycobacterium tuberculosis RG PCR kit in a low incidence setting: a retrospective monocentric study JF - Scientific Reports N2 - Tuberculosis (TB) and the spread of Mycobacterium tuberculosis complex (MTBC) strains resistant against rifampin (RIF) and isoniazid (INH) pose a serious threat to global health. However, rapid and reliable MTBC detection along with RIF/INH susceptibility testing are challenging in low prevalence countries due to the higher rate of false positives. Here, we provide the first performance data for the artus MTBC PCR assay in a low prevalence setting. We analyze 1323 respiratory and 311 non-respiratory samples with the artus MTBC PCR assay as well as by mycobacterial culture and microscopy. We propose retesting of specimens in duplicate and consideration of a determined cycle-threshold value cut-off greater than 34, as this significantly increases accuracy, specificity, and negative predictive value without affecting sensitivity. Furthermore, we tested fourteen MTBC positive samples with the GenoType MTBDRplus test and demonstrate that using an identical DNA extraction protocol for both assays does not impair downstream genotypic testing for RIF and INH susceptibility. In conclusion, our procedure optimizes the use of the artus MTB assay with workload efficient methods in a low incidence setting. Combining the modified artus MTB with the GenoType MTBDRplus assays allows rapid and accurate detection of MTBC and RIF/INH resistance. KW - laboratory techniques and procedures KW - Tuberculosis Y1 - 2017 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-159248 VL - 7 IS - 14127 ER - TY - JOUR A1 - Stijnis, Kees A1 - Dijkmans, Anneke C. A1 - Bart, Aldert A1 - Brosens, Lodewijk A. A. A1 - Muntau, Birgit A1 - Schoen, Christoph A1 - Barth, Thomas F. A1 - van Gulik, Thomas A1 - van Gool, Tom A1 - Grobusch, Martin P. A1 - Tappe, Dennis T1 - Echinococcus vogeli in Immigrant from Suriname to the Netherlands JF - Emerging Infectious Diseases KW - alveolar echinococcosis KW - monoclonal antibody KW - multilocularis Y1 - 2015 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-143953 VL - 21 IS - 3 ER - TY - JOUR A1 - Tappe, Dennis A1 - Meyer, Michael A1 - Oesterlein, Anett A1 - Jaye, Assan A1 - Frosch, Matthias A1 - Schoen, Christoph A1 - Pantchev, Nikola T1 - Transmission of Armillifer armillatus Ova at Snake Farm, The Gambia, West Africa JF - Emerging Infectious Diseases N2 - Visceral pentastomiasis caused by Armillifer armillatus larvae was diagnosed in 2 dogs in The Gambia. Parasites were subjected to PCR; phylogenetic analysis confirmed relatedness with branchiurans/crustaceans. Our investigation highlights transmission of infective A. armillatus ova to dogs and, by serologic evidence, also to 1 human, demonstrating a public health concern. KW - Pentastomiasis Y1 - 2011 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-142804 N1 - All material published in Emerging Infectious Diseases is in the public domain and may be used and reprinted without special permission; proper citation, however, is required. VL - 17 IS - 2 ER - TY - JOUR A1 - Heisig, Martin A1 - Frentzen, Alexa A1 - Bergmann, Birgit A1 - Gentschev, Katharina Ivaylo A1 - Hotz, Christian A1 - Schoen, Christoph A1 - Stritzker, Jochen A1 - Fensterle, Joachim A1 - Rapp, Ulf R. A1 - Goebel, Werner T1 - Specific antibody-receptor interactions trigger InlAB-independent uptake of Listeria monocytogenes into tumor cell lines N2 - Background: Specific cell targeting is an important, yet unsolved problem in bacteria-based therapeutic applications, like tumor or gene therapy. Here, we describe the construction of a novel, internalin A and B (InlAB)-deficient Listeria monocytogenes strain (Lm-spa+), which expresses protein A of Staphylococcus aureus (SPA) and anchors SPA in the correct orientation on the bacterial cell surface. Results: This listerial strain efficiently binds antibodies allowing specific interaction of the bacterium with the target recognized by the antibody. Binding of Trastuzumab (Herceptin®) or Cetuximab (Erbitux®) to Lm-spa+, two clinically approved monoclonal antibodies directed against HER2/neu and EGFR/HER1, respectively, triggers InlABindependent internalization into non-phagocytic cancer cell lines overexpressing the respective receptors. Internalization, subsequent escape into the host cell cytosol and intracellular replication of these bacteria are as efficient as of the corresponding InlAB-positive, SPA-negative parental strain. This specific antibody/receptormediated internalization of Lm-spa+ is shown in the murine 4T1 tumor cell line, the isogenic 4T1-HER2 cell line as well as the human cancer cell lines SK-BR-3 and SK-OV-3. Importantly, this targeting approach is applicable in a xenograft mouse tumor model after crosslinking the antibody to SPA on the listerial cell surface. Conclusions: Binding of receptor-specific antibodies to SPA-expressing L. monocytogenes may represent a promising approach to target L. monocytogenes to host cells expressing specific receptors triggering internalization. KW - Listeria monocytogenes Y1 - 2011 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-68705 ER - TY - JOUR A1 - Biju, Joseph A1 - Schwarz, Roland A1 - Linke, Burkhard A1 - Blom, Jochen A1 - Becker, Anke A1 - Claus, Heike A1 - Goesmann, Alexander A1 - Frosch, Matthias A1 - Müller, Tobias A1 - Vogel, Ulrich A1 - Schoen, Christoph T1 - Virulence Evolution of the Human Pathogen Neisseria meningitidis by Recombination in the Core and Accessory Genome JF - PLoS One N2 - Background Neisseria meningitidis is a naturally transformable, facultative pathogen colonizing the human nasopharynx. Here, we analyze on a genome-wide level the impact of recombination on gene-complement diversity and virulence evolution in N. meningitidis. We combined comparative genome hybridization using microarrays (mCGH) and multilocus sequence typing (MLST) of 29 meningococcal isolates with computational comparison of a subset of seven meningococcal genome sequences. Principal Findings We found that lateral gene transfer of minimal mobile elements as well as prophages are major forces shaping meningococcal population structure. Extensive gene content comparison revealed novel associations of virulence with genetic elements besides the recently discovered meningococcal disease associated (MDA) island. In particular, we identified an association of virulence with a recently described canonical genomic island termed IHT-E and a differential distribution of genes encoding RTX toxin- and two-partner secretion systems among hyperinvasive and non-hyperinvasive lineages. By computationally screening also the core genome for signs of recombination, we provided evidence that about 40% of the meningococcal core genes are affected by recombination primarily within metabolic genes as well as genes involved in DNA replication and repair. By comparison with the results of previous mCGH studies, our data indicated that genetic structuring as revealed by mCGH is stable over time and highly similar for isolates from different geographic origins. Conclusions Recombination comprising lateral transfer of entire genes as well as homologous intragenic recombination has a profound impact on meningococcal population structure and genome composition. Our data support the hypothesis that meningococcal virulence is polygenic in nature and that differences in metabolism might contribute to virulence. KW - population genetics KW - DNA recombination KW - meningococcal disease KW - recombinant proteins KW - genomic databases KW - comparative genomics KW - neisseria meningitidis KW - homologous recombination Y1 - 2011 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-137960 VL - 6 IS - 4 ER - TY - JOUR A1 - Schoen, Christoph A1 - Kischkies, Laura A1 - Elias, Johannes A1 - Ampattu, Biju Joseph T1 - Metabolism and virulence in Neisseria meningitidis N2 - A longstanding question in infection biology addresses the genetic basis for invasive behavior in commensal pathogens. A prime example for such a pathogen is Neisseria meningitidis. On the one hand it is a harmless commensal bacterium exquisitely adapted to humans, and on the other hand it sometimes behaves like a ferocious pathogen causing potentially lethal disease such as sepsis and acute bacterial meningitis. Despite the lack of a classical repertoire of virulence genes in N. meningitidis separating commensal from invasive strains, molecular epidemiology suggests that carriage and invasive strains belong to genetically distinct populations. In recent years, it has become increasingly clear that metabolic adaptation enables meningococci to exploit host resources, supporting the concept of nutritional virulence as a crucial determinant of invasive capability. Here, we discuss the contribution of core metabolic pathways in the context of colonization and invasion with special emphasis on results from genome-wide surveys. The metabolism of lactate, the oxidative stress response, and, in particular, glutathione metabolism as well as the denitrification pathway provide examples of how meningococcal metabolism is intimately linked to pathogenesis. We further discuss evidence from genome-wide approaches regarding potential metabolic differences between strains from hyperinvasive and carriage lineages and present new data assessing in vitro growth differences of strains from these two populations. We hypothesize that strains from carriage and hyperinvasive lineages differ in the expression of regulatory genes involved particularly in stress responses and amino acid metabolism under infection conditions. KW - Neisseria meningitidis KW - virulence KW - pathometabolism KW - oxidative stress KW - glutathione KW - γ-glutamyl cycle KW - glutamate dehydrogenase KW - nitrite respiration Y1 - 2014 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-113118 ER - TY - JOUR A1 - Marincola, Gabriella A1 - Liong, Olivia A1 - Schoen, Christoph A1 - Abouelfetouh, Alaa A1 - Hamdy, Aisha A1 - Wencker, Freya D. R. A1 - Marciniak, Tessa A1 - Becker, Karsten A1 - Köck, Robin A1 - Ziebuhr, Wilma T1 - Antimicrobial Resistance Profiles of Coagulase-Negative Staphylococci in Community-Based Healthy Individuals in Germany JF - Frontiers in Public Health N2 - Coagulase-negative staphylococci (CoNS) are common opportunistic pathogens, but also ubiquitous human and animal commensals. Infection-associated CoNS from healthcare environments are typically characterized by pronounced antimicrobial resistance (AMR) including both methicillin- and multidrug-resistant isolates. Less is known about AMR patterns of CoNS colonizing the general population. Here we report on AMR in commensal CoNS recovered from 117 non-hospitalized volunteers in a region of Germany with a high livestock density. Among the 69 individuals colonized with CoNS, 29 had reported contacts to either companion or farm animals. CoNS were selectively cultivated from nasal swabs, followed by species definition by 16S rDNA sequencing and routine antibiotic susceptibility testing. Isolates displaying phenotypic AMR were further tested by PCR for presence of selected AMR genes. A total of 127 CoNS were isolated and Staphylococcus epidermidis (75%) was the most common CoNS species identified. Nine isolates (7%) were methicillin-resistant (MR) and carried the mecA gene, with seven individuals (10%) being colonized with at least one MR-CoNS isolate. While resistance against gentamicin, phenicols and spectinomycin was rare, high resistance rates were found against tetracycline (39%), erythromycin (33%) and fusidic acid (24%). In the majority of isolates, phenotypic resistance could be associated with corresponding AMR gene detection. Multidrug-resistance (MDR) was observed in 23% (29/127) of the isolates, with 33% (23/69) of the individuals being colonized with MDR-CoNS. The combined data suggest that MR- and MDR-CoNS are present in the community, with previous animal contact not significantly influencing the risk of becoming colonized with such isolates. KW - coagulase-negative staphylococci KW - antimicrobial resistance KW - One Health KW - community settings KW - Germany Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-240881 SN - 2296-2565 VL - 9 ER - TY - JOUR A1 - Ampattu, Biju Joseph A1 - Hagmann, Laura A1 - Liang, Chunguang A1 - Dittrich, Marcus A1 - Schlüter, Andreas A1 - Blom, Jochen A1 - Krol, Elizaveta A1 - Goesmann, Alexander A1 - Becker, Anke A1 - Dandekar, Thomas A1 - Müller, Tobias A1 - Schoen, Christoph T1 - Transcriptomic buffering of cryptic genetic variation contributes to meningococcal virulence JF - BMC Genomics N2 - Background: Commensal bacteria like Neisseria meningitidis sometimes cause serious disease. However, genomic comparison of hyperinvasive and apathogenic lineages did not reveal unambiguous hints towards indispensable virulence factors. Here, in a systems biological approach we compared gene expression of the invasive strain MC58 and the carriage strain α522 under different ex vivo conditions mimicking commensal and virulence compartments to assess the strain-specific impact of gene regulation on meningococcal virulence. Results: Despite indistinguishable ex vivo phenotypes, both strains differed in the expression of over 500 genes under infection mimicking conditions. These differences comprised in particular metabolic and information processing genes as well as genes known to be involved in host-damage such as the nitrite reductase and numerous LOS biosynthesis genes. A model based analysis of the transcriptomic differences in human blood suggested ensuing metabolic flux differences in energy, glutamine and cysteine metabolic pathways along with differences in the activation of the stringent response in both strains. In support of the computational findings, experimental analyses revealed differences in cysteine and glutamine auxotrophy in both strains as well as a strain and condition dependent essentiality of the (p)ppGpp synthetase gene relA and of a short non-coding AT-rich repeat element in its promoter region. Conclusions: Our data suggest that meningococcal virulence is linked to transcriptional buffering of cryptic genetic variation in metabolic genes including global stress responses. They further highlight the role of regulatory elements for bacterial virulence and the limitations of model strain approaches when studying such genetically diverse species as N. meningitidis. KW - neisseria meningitidis KW - MITE KW - virulenceregulatory evolution KW - systems biology KW - metabolism KW - cryptic KW - genetic variation KW - stringent response KW - relA Y1 - 2017 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-157534 VL - 18 IS - 282 ER - TY - JOUR A1 - Klughammer, Johanna A1 - Dittrich, Marcus A1 - Blom, Jochen A1 - Mitesser, Vera A1 - Vogel, Ulrich A1 - Frosch, Matthias A1 - Goesmann, Alexander A1 - Müller, Tobias A1 - Schoen, Christoph T1 - Comparative genome sequencing reveals within-host genetic changes in Neisseria meningitidis during invasive disease JF - PLoS ONE N2 - Some members of the physiological human microbiome occasionally cause life-threatening disease even in immunocompetent individuals. A prime example of such a commensal pathogen is Neisseria meningitidis, which normally resides in the human nasopharynx but is also a leading cause of sepsis and epidemic meningitis. Using N. meningitidis as model organism, we tested the hypothesis that virulence of commensal pathogens is a consequence of within host evolution and selection of invasive variants due to mutations at contingency genes, a mechanism called phase variation. In line with the hypothesis that phase variation evolved as an adaptation to colonize diverse hosts, computational comparisons of all 27 to date completely sequenced and annotated meningococcal genomes retrieved from public databases showed that contingency genes are indeed enriched for genes involved in host interactions. To assess within-host genetic changes in meningococci, we further used ultra-deep whole-genome sequencing of throat-blood strain pairs isolated from four patients suffering from invasive meningococcal disease. We detected up to three mutations per strain pair, affecting predominantly contingency genes involved in type IV pilus biogenesis. However, there was not a single (set) of mutation(s) that could invariably be found in all four pairs of strains. Phenotypic assays further showed that these genetic changes were generally not associated with increased serum resistance, higher fitness in human blood ex vivo or differences in the interaction with human epithelial and endothelial cells in vitro. In conclusion, we hypothesize that virulence of meningococci results from accidental emergence of invasive variants during carriage and without within host evolution of invasive phenotypes during disease progression in vivo. KW - blood KW - comparative genomics KW - throat KW - genetic loci KW - Neisseria meningitidis KW - genomic libraries KW - genome sequencing KW - sequence assembly tools Y1 - 2017 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-159547 VL - 12 IS - 1 ER - TY - JOUR A1 - Bauriedl, Saskia A1 - Gerovac, Milan A1 - Heidrich, Nadja A1 - Bischler, Thorsten A1 - Barquist, Lars A1 - Vogel, Jörg A1 - Schoen, Christoph T1 - The minimal meningococcal ProQ protein has an intrinsic capacity for structure-based global RNA recognition JF - Nature Communications N2 - FinO-domain proteins are a widespread family of bacterial RNA-binding proteins with regulatory functions. Their target spectrum ranges from a single RNA pair, in the case of plasmid-encoded FinO, to global RNA regulons, as with enterobacterial ProQ. To assess whether the FinO domain itself is intrinsically selective or promiscuous, we determine in vivo targets of Neisseria meningitidis, which consists of solely a FinO domain. UV-CLIP-seq identifies associations with 16 small non-coding sRNAs and 166 mRNAs. Meningococcal ProQ predominantly binds to highly structured regions and generally acts to stabilize its RNA targets. Loss of ProQ alters transcript levels of >250 genes, demonstrating that this minimal ProQ protein impacts gene expression globally. Phenotypic analyses indicate that ProQ promotes oxidative stress resistance and DNA damage repair. We conclude that FinO domain proteins recognize some abundant type of RNA shape and evolve RNA binding selectivity through acquisition of additional regions that constrain target recognition. FinO-domain proteins are bacterial RNA-binding proteins with a wide range of target specificities. Here, the authors employ UV CLIP-seq and show that minimal ProQ protein of Neisseria meningitidis binds to various small non-coding RNAs and mRNAs involved in virulence. KW - Neisseria meningitidis KW - natural transformation KW - dual function KW - FinO family KW - HFQ KW - chaperone KW - transcriptome KW - regulator KW - sequence KW - in vivo Y1 - 2020 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-230040 VL - 11 ER -