TY - JOUR
T1 - Relationship between the Tsh autotransporter and pathogenicity of avian Escherichia coli and localization and analysis of the tsh genetic region
AU - Dozois, Charles M.
AU - Dho-Moulin, Maryvonne
AU - Brée, Annie
AU - Fairbrother, John M.
AU - Desautels, Clarisse
AU - Curtiss, Roy
PY - 2000/7
Y1 - 2000/7
N2 - The temperature-sensitive hemagglutinin Tsh is a member of the autotransporter group of proteins and was first identified in avian- pathogenic Escherichia coli (APEC) strain χ7122. The prevalence of tsh was investigated in 300 E. coli isolates of avian origin and characterized for virulence in a 1-day-old chick lethality test. Results indicate that among the tsh-positive APEC isolates, 90.6% belonged to the highest virulence class. Experimental inoculation of chickens with χ7122 and an isogenic tsh mutant demonstrated that Tsh may contribute to the development of lesions within the air sacs of birds but is not required for subsequent generalized infection manifesting as perihepatitis, pericarditis, and septicemia. Conjugation and hybridization experiments revealed that the tsh gene is located on a CoIV-type plasmid in many of the APEC strains studied, including strain χ7122, near the colicin V genes in most of these strains. DNA sequences flanking the tsh gene of strain χ7122 include complete and partial insertion sequences and phage-related DNA sequences, some of which were also found on virulence plasmids and pathogenicity islands present in various E. coli pathotypes and other pathogenic members of the Enterobacteriaceae. These results demonstrate that the tsh gene is frequently located on the CoIV virulence plasmid in APEC and suggest a possible role of Tsh in the pathogenicity of E. coli for chickens in the early stages of infection.
AB - The temperature-sensitive hemagglutinin Tsh is a member of the autotransporter group of proteins and was first identified in avian- pathogenic Escherichia coli (APEC) strain χ7122. The prevalence of tsh was investigated in 300 E. coli isolates of avian origin and characterized for virulence in a 1-day-old chick lethality test. Results indicate that among the tsh-positive APEC isolates, 90.6% belonged to the highest virulence class. Experimental inoculation of chickens with χ7122 and an isogenic tsh mutant demonstrated that Tsh may contribute to the development of lesions within the air sacs of birds but is not required for subsequent generalized infection manifesting as perihepatitis, pericarditis, and septicemia. Conjugation and hybridization experiments revealed that the tsh gene is located on a CoIV-type plasmid in many of the APEC strains studied, including strain χ7122, near the colicin V genes in most of these strains. DNA sequences flanking the tsh gene of strain χ7122 include complete and partial insertion sequences and phage-related DNA sequences, some of which were also found on virulence plasmids and pathogenicity islands present in various E. coli pathotypes and other pathogenic members of the Enterobacteriaceae. These results demonstrate that the tsh gene is frequently located on the CoIV virulence plasmid in APEC and suggest a possible role of Tsh in the pathogenicity of E. coli for chickens in the early stages of infection.
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U2 - 10.1128/IAI.68.7.4145-4154.2000
DO - 10.1128/IAI.68.7.4145-4154.2000
M3 - Article
C2 - 10858231
AN - SCOPUS:0033932231
SN - 0019-9567
VL - 68
SP - 4145
EP - 4154
JO - Infection and immunity
JF - Infection and immunity
IS - 7
ER -