@article{SchmidtRabschBroekeretal.2016, author = {Schmidt, Andreas and Rabsch, Wolfgang and Br{\"o}ker, Nina Kristin and Barbirz, Stefanie}, title = {Bacteriophage tailspike protein based assay to monitor phase variable glucosylations in Salmonella O-antigens}, series = {BMC microbiology}, volume = {16}, journal = {BMC microbiology}, publisher = {BioMed Central}, address = {London}, issn = {1471-2180}, doi = {10.1186/s12866-016-0826-0}, pages = {2214 -- 2226}, year = {2016}, abstract = {Background: Non-typhoid Salmonella Typhimurium (S. Typhimurium) accounts for a high number of registered salmonellosis cases, and O-serotyping is one important tool for monitoring epidemiology and spread of the disease. Moreover, variations in glucosylated O-antigens are related to immunogenicity and spread in the host. However, classical autoagglutination tests combined with the analysis of specific genetic markers cannot always reliably register phase variable glucose modifications expressed on Salmonella O-antigens and additional tools to monitor O-antigen glucosylation phenotypes of S. Typhimurium would be desirable. Results: We developed a test for the phase variable O-antigen glucosylation state of S. Typhimurium using the tailspike proteins (TSP) of Salmonella phages 9NA and P22. We used this ELISA like tailspike adsorption (ELITA) assay to analyze a library of 44 Salmonella strains. ELITA was successful in discriminating strains that carried glucose 1-6 linked to the galactose of O-polysaccharide backbone (serotype O1) from non-glucosylated strains. This was shown by O-antigen compositional analyses of the respective strains with mass spectrometry and capillary electrophoresis. The ELITA test worked rapidly in a microtiter plate format and was highly O-antigen specific. Moreover, TSP as probes could also detect glucosylated strains in flow cytometry and distinguish multiphasic cultures differing in their glucosylation state. Conclusions: Tailspike proteins contain large binding sites with precisely defined specificities and are therefore promising tools to be included in serotyping procedures as rapid serotyping agents in addition to antibodies. In this study, 9NA and P22TSP as probes could specifically distinguish glucosylation phenotypes of Salmonella on microtiter plate assays and in flow cytometry. This opens the possibility for flow sorting of cell populations for subsequent genetic analyses or for monitoring phase variations during large scale O-antigen preparations necessary for vaccine production.}, language = {en} } @article{SchmidtRabschBroekeretal.2016, author = {Schmidt, Andreas and Rabsch, Wolfgang and Broeker, Nina K. and Barbirz, Stefanie}, title = {Bacteriophage tailspike protein based assay to monitor phase variable glucosylations in Salmonella O-antigens}, series = {BMC microbiology}, volume = {16}, journal = {BMC microbiology}, publisher = {BioMed Central}, address = {London}, issn = {1471-2180}, doi = {10.1186/s12866-016-0826-0}, pages = {11}, year = {2016}, abstract = {Background Non-typhoid Salmonella Typhimurium (S. Typhimurium) accounts for a high number of registered salmonellosis cases, and O-serotyping is one important tool for monitoring epidemiology and spread of the disease. Moreover, variations in glucosylated O-antigens are related to immunogenicity and spread in the host. However, classical autoagglutination tests combined with the analysis of specific genetic markers cannot always reliably register phase variable glucose modifications expressed on Salmonella O-antigens and additional tools to monitor O-antigen glucosylation phenotypes of S. Typhimurium would be desirable. Results We developed a test for the phase variable O-antigen glucosylation state of S. Typhimurium using the tailspike proteins (TSP) of Salmonella phages 9NA and P22. We used this ELISA like tailspike adsorption (ELITA) assay to analyze a library of 44 Salmonella strains. ELITA was successful in discriminating strains that carried glucose 1-6 linked to the galactose of O-polysaccharide backbone (serotype O1) from non-glucosylated strains. This was shown by O-antigen compositional analyses of the respective strains with mass spectrometry and capillary electrophoresis. The ELITA test worked rapidly in a microtiter plate format and was highly O-antigen specific. Moreover, TSP as probes could also detect glucosylated strains in flow cytometry and distinguish multiphasic cultures differing in their glucosylation state. Conclusions Tailspike proteins contain large binding sites with precisely defined specificities and are therefore promising tools to be included in serotyping procedures as rapid serotyping agents in addition to antibodies. In this study, 9NA and P22TSP as probes could specifically distinguish glucosylation phenotypes of Salmonella on microtiter plate assays and in flow cytometry. This opens the possibility for flow sorting of cell populations for subsequent genetic analyses or for monitoring phase variations during large scale O-antigen preparations necessary for vaccine production.}, language = {en} } @misc{Schmidt2016, type = {Master Thesis}, author = {Schmidt, Andreas}, title = {Udmurt as an OV language}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-89465}, school = {Universit{\"a}t Potsdam}, pages = {iii, 94}, year = {2016}, abstract = {This is the first study to investigate Hubert Haider's (2000, 2010, 2013, 2014) proposed systematic differences between OV and VO language in a family other than Germanic. Its aim is to gather evidence on whether basic word order is predictive of further properties of a language. The languages under investigation are the Finno-Ugric languages Udmurt (as an OV language) and Finnish (as a VO language). Counter to Kayne (1994), Haider proposes that the structure of a sentence with a head-final VP is fundamentally different from that of a sentence with a head-initial VP, e.g., OV languages do not exhibit a VP-shell structure, and they do not employ a TP layer with a structural subject position. Haider's proposed structural differences are said to result in the following empirically testable differences: (a) VP: the availability of VP-internal adverbial intervention and scrambling only in OV-VPs; (b) subjects: the lack of certain subject-object asymmetries in OV languages, i.e., lack of the subject condition and lack of superiority effects; (c) V-complexes: the availability of partial predicate fronting only in OV languages; different orderings between selecting and selected verbs; the intervention of non-verbal material between verbs only in VO languages; (d) V-particles: differences in the distribution of resultative phrases and verb particles. Udmurt and Finnish behave in line with Haider's predictions with regard to the status of the subject, with regard to the order of selecting and selected verbs, and with regard to the availability of partial predicate fronting. Moreover, Udmurt allows for adverbial intervention and scrambling, as predicted, whereas the status of these properties in Finnish could not be reliably determined due to obligatory V-to-T. There is also counterevidence to Haider's predictions: Udmurt allows for non-verbal material between verbs, and the distribution of resultative phrases and verb particles is essentially as free as the distribution of adverbial phrases in both Finno-Ugric languages. As such, Haider's theory is not falsified by the data from Udmurt and Finnish (except for his theory on verb particles), but it is also not fully supported by the data.}, language = {en} }