Prevalence of vacuolating cytotoxin production and distribution of distinct vacA alleles in Helicobacter pylori from China.
Studies of Helicobacter pylori from the West have linked production of vacuolating cytotoxin and a particular signal sequence (s1a) allele of the underlying vacA gene to peptic ulcer disease (PUD). Among Chinese H. pylori, most isolates from both PUD and gastritis patients were toxigenic (35/46 and 29/35, respectively). Polymerase chain reaction and DNA sequencing showed that 95 of 96 isolates carried vacA s1a alleles. In the mid-region, 78 of 96 isolates carried m2; 14 were m1-like but only 87% identical (DNA-level) to classical m1 and were designated m1b; the other 4 were unusual hybrids (m1b-type proximal, m2-type distal). Isolates with m1b and m1b-m2 alleles produced higher levels of vacuolating activity than did isolates with m2 alleles (P < .01). There was no association between any vacA allele and disease. These results suggest that the composition of H. pylori gene pools varies geographically and that other as-yet-unknown polymorphic H. pylori genes are important in PUD.
Pan
Z J
ZJ
Department of Molecular Microbiology, Washington University School of Medicine, St. Louis, Missouri 63110, USA. Pan@borcim.wustl.edu
Berg
D E
DE
van der Hulst
R W
RW
Su
W W
WW
Raudonikiene
A
A
Xiao
S D
SD
Dankert
J
J
Tytgat
G N
GN
van der Ende
A
A
D000483:Alleles; D001426:Bacterial Proteins / Q000096:biosynthesis / Q000235:genetics* / Q000633:toxicity; D001427:Bacterial Toxins / Q000096:biosynthesis / Q000235:genetics* / Q000633:toxicity; D001483:Base Sequence; D002681:China / Q000453:epidemiology; D003603:Cytotoxins / Q000096:biosynthesis / Q000235:genetics* / Q000633:toxicity; D004269:DNA, Bacterial; D005756:Gastritis / Q000382:microbiology; D006367:HeLa Cells; D016481:Helicobacter Infections / Q000453:epidemiology / Q000382:microbiology*; D016480:Helicobacter pylori / Q000235:genetics* / Q000302:isolation & purification; D006801:Humans; D008969:Molecular Sequence Data; D010437:Peptic Ulcer / Q000382:microbiology; D010641:Phenotype; D015995:Prevalence; D012689:Sequence Homology, Nucleic Acid; D014617:Vacuoles
D001426:Bacterial Proteins; D001427:Bacterial Toxins; D003603:Cytotoxins; D004269:DNA, Bacterial; C074689:VacA protein, Helicobacter pylori