HIGH-LEVEL GENETIC DIVERSITY IN THE VAPD CHROMOSOMAL REGION OF HELICOBACTER-PYLORI

Authors
Citation
P. Cao et Tl. Cover, HIGH-LEVEL GENETIC DIVERSITY IN THE VAPD CHROMOSOMAL REGION OF HELICOBACTER-PYLORI, Journal of bacteriology, 179(9), 1997, pp. 2852-2856
Citations number
47
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Microbiology
Journal title
ISSN journal
0021-9193
Volume
179
Issue
9
Year of publication
1997
Pages
2852 - 2856
Database
ISI
SICI code
0021-9193(1997)179:9<2852:HGDITV>2.0.ZU;2-Z
Abstract
Helicobacter pylori isolates from different patients are characterized By diversity in the nucleotide sequences of individual genes, variati on in genome size, and variation in gene order, Genetic diversity is p articularly striking in vacuolating cytotoxin (vacA) alleles, In this study, five open reading frames (ORFs) were identified within a 4,2-kb region downstream from vacA in H. pylori 60190, One of these ORFs was closely related to the virulence-associated protein D (vapD) gene of Dichelobacter nodosus (64.9% nucleotide identity), A probe derived fro m vapD of H. pylori 60190 hybridized with only 19 (61.3%) of 31 H. pyl ori strains tested, Sequence analysis of the vapD region in vapD-negat ive H. pylori strains revealed that there were two different families of similar to 0.5-kb DNA segments, which were both unrelated to vapD. The presence of vapD was not associated with any specific family of va cA alleles, These findings are consistent with a recombinational popul ation structure for H. pylori.