title: Vacuolating toxin production in clinical isolates of Helicobacter pylori with different vacA genotypes.
abstract: A vacuolating cytotoxin encoded by vacA in Helicobacter pylori is known as a potential virulent determinant. The relationship between different vacA alleles, vacuolating ability, and H. pylori-related diseases was investigated. Genetic analysis of 119 isolates from Taiwanese patients revealed that 104 strains were s1a/m2, 13 strains were characterized as the s1a/m1T type, which was more homologous to the s1a/m1 strains, and 2 were characterized as the s1a/m1Tm2 chimeric type. Production of high-grade cytotoxin among 11 strains with s1a/m1T was higher (72.7%) than among 66 strains with s1a/m2 (21.2%) (P < .01). Peptic ulcer occurred in 76.9% of 13 patients with s1a/m1T strains compared with 46.2% of 104 patients with s1a/m2 strains (P < .05). These results suggest that s1a/m1T strains are associated with increased cytotoxic activity and higher ulcer prevalence than are s1a/m2 strains.
authors.affiliation: Department of Life Science, National Tsing Hua University, Hsinchu, Taiwan, Republic of China.
authors.forename: H J
authors.initials: HJ
authors.lastname: Wang
authors.forename: C H
authors.initials: CH
authors.lastname: Kuo
authors.forename: A A
authors.initials: AA
authors.lastname: Yeh
authors.forename: P C
authors.initials: PC
authors.lastname: Chang
authors.forename: W C
authors.initials: WC
authors.lastname: Wang
mesh_terms: D000595:Amino Acid Sequence; D001426:Bacterial Proteins / Q000096:biosynthesis / Q000235:genetics* / Q000633:toxicity; D001427:Bacterial Toxins / Q000096:biosynthesis / Q000235:genetics* / Q000633:toxicity; D001483:Base Sequence; D003603:Cytotoxins / Q000096:biosynthesis / Q000235:genetics* / Q000633:toxicity; D004269:DNA, Bacterial; D004415:Dyspepsia / Q000382:microbiology; D005838:Genotype; D006367:HeLa Cells; D016481:Helicobacter Infections / Q000382:microbiology*; D016480:Helicobacter pylori / Q000235:genetics* / Q000302:isolation & purification / Q000472:pathogenicity; D006801:Humans; D008969:Molecular Sequence Data; D010437:Peptic Ulcer / Q000382:microbiology; D017422:Sequence Analysis, DNA; D017386:Sequence Homology, Amino Acid; D012689:Sequence Homology, Nucleic Acid; D013274:Stomach Neoplasms / Q000382:microbiology; D014617:Vacuoles
chemical_list: D001426:Bacterial Proteins; D001427:Bacterial Toxins; D003603:Cytotoxins; D004269:DNA, Bacterial; C074689:VacA protein, Helicobacter pylori