title: Understanding the dimorphic lifestyles of human gastric pathogen Helicobacter pylori using the SWATH-based proteomics approach.
abstract: Helicobacter pylori may reside in the human stomach as two morphological forms: the culturable spiral form and the viable but non-culturable (VBNC) coccoid form. This bacterium transforms from spiral to coccoid under in vitro suboptimal conditions. However, both spiral and coccoid have demonstrated its infectivity in laboratory animals, suggesting that coccoid may potentially be involved in the transmission of H. pylori. To determine the relevance of the coccoid form in viability and infectivity, we compared the protein profiles of H. pylori coccoids obtained from prolonged (3-month-old) culture with that of 3-day-old spirals of two H. pylori standard strains using SWATH (Sequential Window Acquisition of all Theoretical mass spectra)-based approach. The protein profiles reveal that the coccoids retained basal level of metabolic proteins and also high level of proteins that participate in DNA replication, cell division and biosynthesis demonstrating that coccoids are viable. Most interestingly, these data also indicate that the H. pylori coccoids possess higher level of proteins that are involved in virulence and carcinogenesis than their spiral counterparts. Taken together, these findings have important implications in the understanding on the pathogenesis of H. pylori-induced gastroduodenal diseases, as well as the probable transmission mode of this bacterium.
authors.affiliation: Department of Medical Microbiology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia.
authors.forename: Mun Fai
authors.initials: MF
authors.lastname: Loke
authors.affiliation: Department of Microbiology and Immunology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore.
authors.forename: Chow Goon
authors.initials: CG
authors.lastname: Ng
authors.affiliation: Department of Medical Microbiology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia.
authors.forename: Yeespana
authors.initials: Y
authors.lastname: Vilashni
authors.affiliation: AB SCIEX Ltd, 10 Biopolis Rd, Singapore 138670, Singapore.
authors.forename: Justin
authors.initials: J
authors.lastname: Lim
authors.affiliation: Department of Microbiology and Immunology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore.
authors.forename: Bow
authors.initials: B
authors.lastname: Ho
mesh_terms: D001426:Bacterial Proteins / Q000032:analysis* / Q000096:biosynthesis / Q000235:genetics; D001431:Bacteriological Techniques; D002473:Cell Wall / Q000378:metabolism; D004261:DNA Replication; D004269:DNA, Bacterial / Q000378:metabolism; D015964:Gene Expression Regulation, Bacterial; D016480:Helicobacter pylori / Q000187:drug effects / Q000235:genetics / Q000502:physiology* / Q000648:ultrastructure; D006801:Humans; D013058:Mass Spectrometry / Q000379:methods*; D053858:Metabolic Networks and Pathways; D009532:Nickel / Q000494:pharmacology; D040901:Proteomics / Q000379:methods*; D014774:Virulence
chemical_list: D001426:Bacterial Proteins; D004269:DNA, Bacterial; D009532:Nickel