title: Simultaneous detection of Bacteroides fragilis group species by leuB-directed PCR.
abstract: Bacteroides species, saccharolytic Gram-negative obligate anaerobes, are frequently isolated from human infections such as peritonitis, abscesses and bacteremia. Among the species in the genus Bacteroides, the species called "B. fragilis group" are particularly involved in human infections and are medically important because they account for a major part of anaerobic isolates from clinical specimens. The purpose of this study was to develop PCR primers that specifically and simultaneously amplify the beta -isopropylmalate dehydrogenase gene leuB in B. fragilis group species. We determined partial nucleotide sequences of leuB genes and compared them in seventeen strains of nine B. fragilis group species, and the regions that are conserved among Bacteroides strains but different from other species were used as a B. fragilis group-specific PCR primer set, BacLBF-BacLBR. Specificity tests of the primer set using 52 phenotypically characterized strains and 75 isolates from rat feces showed only one case each of false-positive and false-negative. The detection limit of the leuB-directed PCR using BacLBF and BacLBR was 3.9 x 10(3) colony-forming units. These results indicate that leuB amplification using BacLBF andBacLBR is a useful tool for rapid diagnosis of Bacteriodes infection and for rapid differential diagnosis of anaerobic infections.
authors.affiliation: Department of Molecular Bacteriology, Institute of Health Biosciences, The University of Tokushima Graduate School, Tokushima, Japan.
authors.forename: Tsuyoshi
authors.initials: T
authors.lastname: Miki
authors.forename: Tomomi
authors.initials: T
authors.lastname: Kuwahara
authors.forename: Haruyuki
authors.initials: H
authors.lastname: Nakayama
authors.forename: Natsumi
authors.initials: N
authors.lastname: Okada
authors.forename: Keiko
authors.initials: K
authors.lastname: Kataoka
authors.forename: Hideki
authors.initials: H
authors.lastname: Arimochi
authors.forename: Yoshinari
authors.initials: Y
authors.lastname: Ohnishi
mesh_terms: D050539:3-Isopropylmalate Dehydrogenase; D000429:Alcohol Oxidoreductases / Q000235:genetics; D000595:Amino Acid Sequence; D000818:Animals; D001439:Bacteroides / Q000145:classification / Q000201:enzymology / Q000235:genetics; D001441:Bacteroides fragilis / Q000201:enzymology / Q000235:genetics* / Q000302:isolation & purification; D001483:Base Sequence; D004269:DNA, Bacterial / Q000235:genetics; D005798:Genes, Bacterial; D006801:Humans; D008969:Molecular Sequence Data; D016133:Polymerase Chain Reaction; D051381:Rats; D012689:Sequence Homology, Nucleic Acid
chemical_list: D004269:DNA, Bacterial; D000429:Alcohol Oxidoreductases; D050539:3-Isopropylmalate Dehydrogenase