Open AccessCharacterization of enteroaggregative Escherichia coli isolates
Author(s) -
Rich Chantal,
FavreBonte Sabine,
Sapena Frédéric,
Joly Bernard,
Forestier Christiane
Publication year - 1999
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.1574-6968.1999.tb13484.x
Subject(s) - escherichia coli , biology , operon , gene , polymerase chain reaction , enteroaggregative escherichia coli , enterotoxin , hybridization probe , molecular cloning , microbiology and biotechnology , dna , enterobacteriaceae , cloning (programming) , heat stable enterotoxin , nucleic acid sequence , peptide sequence , genetics , computer science , programming language
Forty enteraggregative Escherichia coli (EAggEC) previously characterized by their ability to adhere to HEp‐2 cells or/and their hybridization with the 1‐kb EAggEC DNA probe were investigated for the presence of adherence factors and heat‐stable enterotoxin (EAST1)‐encoding genes. Only 45% of the isolates harbored the EAST1‐encoding genes as detected by polymerase chain reaction. None of them hybridized with an AAF/II‐encoding gene specific DNA probe and 35% (14/40) were positive in a PCR assay using primers specific for agg C, an accessory gene of the AAF/I‐encoding operon. Cloning and sequence analysis of the agg A variant from one isolate, EAggEC 457, revealed 68.9% identity between its deduced amino acid sequence and those of the agg A product from the AAF/I‐producing reference strain, E. coli 17.2. No major protein subunit was detected at the surface of EAggEC 457 compared to the bacterial surface extract of E. coli 17.2.