Open AccessVirulence gene profiling of enteroaggregative E scherichia coli heat‐stable enterotoxin 1‐harboring E . coli ( EAST 1 EC ) derived from sporadic diarrheal patients
Author(s) -
Konno Takayuki,
Yatsuyanagi Jun,
Saito Shioko
Publication year - 2012
Publication title -
fems immunology & medical microbiology
Language(s) - English
Resource type - Journals
eISSN - 1574-695X
pISSN - 0928-8244
DOI - 10.1111/j.1574-695x.2011.00913.x
Subject(s) - virulence , enteroaggregative escherichia coli , biology , microbiology and biotechnology , enterotoxin , escherichia coli , pathogenic escherichia coli , diarrhea , bacterial adhesin , gene , hemolysin , enterobacteriaceae , virology , genetics , medicine
Between 2007 and 2009, a total of 2168 E scherichia coli strains derived from diarrheal patients, defined as putative diarrheagenic E . coli ( DEC ), were collected from medical institutions in Akita prefecture, Japan. Thirty five of the strains lacked typical pathogenic determinants of DEC other than astA , which encodes enteroaggregative E. coli ( EA gg EC ) heat‐stable enterotoxin 1 ( EAST 1). These E. coli strains are referred to as EAST 1 EC . Several studies have suggested a role of EAST 1 in diarrhea; however, the correlation between diarrhea and the presence of astA remains inconclusive. To investigate whether EAST 1 EC strains derived from diarrheal patients shared pathogenic factors other than EAST 1, virulence gene profiling of 12 virulence genes – iha , lpfA , ldaG , pilS , pic , pet , irp2 , daa , aah , aid , cdtB and hlyA – was carried out. PCR analysis revealed that four of the 35 EAST 1 EC strains harbored only astA , 24 harbored genes associated with adhesins and intestinal colonization, three strains harbored the gene for α‐hemolysin, and 24 strains harbored the gene for a siderophore. These results indicated that some EAST 1 EC strains harbor various virulence genes associated with distinct E . coli pathotypes, primarily enterohemorrhagic E . coli and EA gg EC , which may represent additional pathogenic determinants of EAST 1 EC .