title: Microevolution of Helicobacter pylori type IV secretion systems in an ulcer disease patient over a ten-year period.
abstract: Helicobacter pylori cagA and vacA genotypes have been used for almost a decade as stable entities to link the severity of gastritis and ulcer disease. We describe here microevolution of the two genomic islands, cag pathogenicity island (cagPAI; 40 kb) and tfs3 (16 kb) from isolates obtained at inclusion (one subclone) and after a 10-year period (two subclones) from a duodenal ulcer patient. Our results indicate microevolution in cagA, cagE, and cag7 genes of the cagPAI and open reading frames G, P, and L in tfs3, which possibly leads to inactivation or pseudogenization of these genes. Interestingly, no significant reduction in the severity of gastroduodenal pathology was found. These results point to an obvious difficulty in correlating the continuously evolving virulence factors such as the cagPAI genes with disease characteristics that appear to remain stable.
authors.affiliation: Pathogen Evolution Lab, CDFD, Nacharam/Gandipet, Hyderabad, India.
authors.forename: Ayesha
authors.initials: A
authors.lastname: Alvi
authors.forename: S Manjulata
authors.initials: SM
authors.lastname: Devi
authors.forename: Irshad
authors.initials: I
authors.lastname: Ahmed
authors.forename: M Abid
authors.initials: MA
authors.lastname: Hussain
authors.forename: Mohammed
authors.initials: M
authors.lastname: Rizwan
authors.forename: Hérve
authors.initials: H
authors.lastname: Lamouliatte
authors.forename: Francis
authors.initials: F
authors.lastname: Mégraud
authors.forename: Niyaz
authors.initials: N
authors.lastname: Ahmed
mesh_terms: D000220:Adaptation, Biological; D000942:Antigens, Bacterial / Q000235:genetics; D001426:Bacterial Proteins / Q000235:genetics; D004269:DNA, Bacterial / Q000737:chemistry / Q000235:genetics; D019143:Evolution, Molecular; D044404:Genomic Islands / Q000235:genetics; D016481:Helicobacter Infections / Q000150:complications / Q000382:microbiology*; D016480:Helicobacter pylori / Q000145:classification* / Q000235:genetics* / Q000302:isolation & purification / Q000472:pathogenicity; D006801:Humans; D008137:Longitudinal Studies; D008969:Molecular Sequence Data; D016366:Open Reading Frames; D010437:Peptic Ulcer / Q000382:microbiology* / Q000473:pathology; D011544:Pseudogenes; D017422:Sequence Analysis, DNA
chemical_list: D000942:Antigens, Bacterial; D001426:Bacterial Proteins; C119842:CAG7 protein, Helicobacter pylori; D004269:DNA, Bacterial; C103937:PicB protein, Helicobacter pylori; C080866:cagA protein, Helicobacter pylori