Open AccessEvaluation of using a short region of the recA gene for rapid and sensitive speciation of dominant bifidobacteria in the human large intestine 1
Author(s) -
Kullen Martin J,
Brady Linda J,
O'Sullivan Daniel J
Publication year - 1997
Publication title -
fems microbiology letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.899
H-Index - 151
eISSN - 1574-6968
pISSN - 0378-1097
DOI - 10.1111/j.1574-6968.1997.tb12670.x
Subject(s) - biology , phylogenetic tree , 16s ribosomal rna , gene , genetics , phylogenetics , ribosomal rna , bifidobacterium , restriction fragment length polymorphism , bifidobacterium longum , polymerase chain reaction , microbiology and biotechnology , bacteria , lactobacillus
The feasibility of intragenerically characterizing bifidobacteria by a comparison of a short region within the recA gene was tested. An ∼300 bp fragment of the recA gene was PCR‐amplified from six species from the genus Bifidobacterium using primers directed to two universally conserved regions of the recA gene. A phylogenetic analysis of the sequenced recA products compared favorably to classification based on the 16S rRNA sequences of the species tested. To apply this rapid methodology to unknown human intestinal bifidobacteria, 46 isolates were randomly chosen from the feces of four subjects and initially characterized by RFLP analysis of a PCR‐amplified region of their 16S RNA genes. From a representative of the dominant RFLP family in each of the subjects, the recA segment was PCR‐amplified, sequenced and phylogenetically analyzed. All four isolates were found to be related to one another and to B. longum and B. infantis . These results illustrate that the recA gene may be useful for intrageneric phylogenetic analysis as well as for the identification of unknown fecal bifidobacteria.