Evidence for extensive resistance gene transfer among Bacteroides spp. and among Bacteroides and other genera in the human colon.

ABSTRACT: Transfer of antibiotic resistance genes by conjugation is thought to play an important role in the spread of resistance. Yet virtually no information is available about the extent to which such horizontal transfers occur in natural settings. In this paper, we show that conjugal gene transfer has made a major contribution to increased antibiotic resistance in Bacteroides species, a numerically predominant group of human colonic bacteria. Over the past 3 decades, carriage of the tetracycline resistance gene, tetQ, has increased from about 30% to more than 80% of strains. Alleles of tetQ in different Bacteroides species, with one exception, were 96 to 100% identical at the DNA sequence level, as expected if horizontal gene transfer was responsible for their spread. Southern blot analyses show

SUBMITTER: Shoemaker NB 

PROVIDER: S-EPMC92621 | biostudies-literature | 2001 Feb

REPOSITORIES: biostudies-literature