ARS | Publication request: Identification and analysis of Escherichia albertii isolates from chicken rinses using polymerase chain reaction, pulse field gel electrophoresis and sequencing a 610bp section of the rpoB gene

Submitted to: American Society for Microbiology General Meeting
Publication Type: Abstract Only
Publication Acceptance Date: May 22, 2011
Publication Date: May 23, 2011
Citation: Lindsey, R.L., Turpin, J.B., Cray, P.J., Meinersmann, R.J. 2011. Identification and analysis of Escherichia albertii isolates from chicken rinses using polymerase chain reaction, pulse field gel electrophoresis and sequencing a 610bp section of the rpoB gene. American Society for Microbiology General Meeting. pg. 119. Poster# 972.

Technical Abstract: Escherichia albertii is a recently described organism that has been associated with diarrhea in humans and with infection and death in birds. It has also been found in healthy birds. E. albertii has been found in two healthy chickens from Australia and a dead chicken from Washington state. The prevalence and clinical importance of E. albertii is not known because it is frequently not identified or incorrectly identified as E. coli, Hafnia alvei and Shigella. This study was designed to identify E. albertii isolates from chicken rinses during an 11 month period in 2009/2010 to learn more about the prevalence of E. albertii. Rinses from1644 chickens were cultured for possible E. albertii isolates. From these rinses 1125 colonies were tested using a multiplex polymerase chain reaction (PCR) for the presence of clpX, lysP and mdh genes. Whenever possible rinses had multiple colonies tested. Isolates positive for these three genes were considered putative positive and analyzed further. Sixty-two isolates were found to be putative positive. Further analysis used PCR to detect intimin (eae), Shiga toxins 1 and 2 (stx1, stx2), heat-stable enterotoxin A (staA), and cytolethal distending toxin (cdtB) genes. Isolates positive for cdtB and eae were analyzed for their antimicrobial resistance phenotypes and pulsed field gel electrophoresis (PFGE) genotypes. We also sought to determine an additional method for positive identification of E. albertii. DNA was extracted from thirty-five (18 of which were a duplicate or triplicate from an original rinse) isolates that carried the expected E. albertii genes and a 610bp section of the rpoB gene was sequenced and 485 bp were analyzed for the presence or absence of fixed differences between E. albertii and other closely related organisms. Fixed differences were found at 12 nucleotide sites. This is the first study to examine the prevalence of E. albertii in a large population of chicken rinses from across the USA. E. albertii isolates were detected in chicken rinses from three out of five regions of the United States. Twelve fixed differences were found in the rpoB gene in isolates that were PCR positive for E. albertii, which could help in positive identification of E. albertii.