The alleles of the bft gene are distributed differently among enterotoxigenic Bacteroides fragilis strains from human sources and can be present in double copies.

ABSTRACT: Enterotoxigenic Bacteroides fragilis (ETBF) strains are associated with diarrheal disease in children. These strains produce a zinc metalloprotease enterotoxin, or fragilysin, that can be detected by a cytotoxicity assay with HT-29 cells. Recently, three different isoforms or variants of the enterotoxin gene, designated bft-1, bft-2, and bft-3, have been identified and sequenced. We used restriction fragment length polymorphism analysis of the PCR-amplified enterotoxin gene to detect the isoforms bft-1 and bft-2 or bft-3 borne by ETBF. By sequencing the portion of the bft gene corresponding to the mature toxin in some strains and applying allele-specific PCR for strains categorized as bft-2 or bft-3, we found in our collection two strains harboring bft-3, a variant that had been described

SUBMITTER: Scotto d'Abusco AS 

PROVIDER: S-EPMC86157 | biostudies-literature | 2000 Feb

REPOSITORIES: biostudies-literature