TY - JOUR
T1 - Functional characterization of the twin-arginine translocation system in campylobacter jejuni
AU - Rajashekara, Gireesh
AU - Drozd, Mary
AU - Gangaiah, Dharanesh
AU - Jeon, Byeonghwa
AU - Liu, Zhe
AU - Zhang, Qijing
PY - 2009/10/1
Y1 - 2009/10/1
N2 - Human campylobacterosis is one of the most commonly occurring types of bacterial food poisoning in the United States and other developed countries. Most human cases are due to Campylobacter jejuni that is commonly found in the gastrointestinal tract of chickens. The twin-arginine translocase (TAT) secretion system uses N-terminal peptide tags with a distinct twin-arginine-containing motif to identify partially or fully folded proteins and directs them across the cytoplasmic membrane. In other bacteria, the TAT system contributes to diverse phenotypes, including virulence, but the role of this secretion system in Campylobacter pathophysiology is still not well defined. Genome sequence of C. jejuni revealed TAT pathway genes as well as several proteins that contain TAT pathway targeting motifs. The predicted Tat substrates are highly conserved among all sequenced C. jejuni strains. Phenotypic analyses revealed that the tatC knockout has defects in biofilm formation, motility, and flagellation, as well as an increased susceptibility to antimicrobials. Additionally, the tatC mutant was defective in survival under osmotic shock, oxidative, and nutrient stresses. Our results also indicated that tatC is essential for C. jejuni to sustain colonization in chickens. These findings suggest that the TAT pathway affects Campylobacter physiology and contributes to stress responses, allowing this fastidious pathogen to adapt to various environmental conditions.
AB - Human campylobacterosis is one of the most commonly occurring types of bacterial food poisoning in the United States and other developed countries. Most human cases are due to Campylobacter jejuni that is commonly found in the gastrointestinal tract of chickens. The twin-arginine translocase (TAT) secretion system uses N-terminal peptide tags with a distinct twin-arginine-containing motif to identify partially or fully folded proteins and directs them across the cytoplasmic membrane. In other bacteria, the TAT system contributes to diverse phenotypes, including virulence, but the role of this secretion system in Campylobacter pathophysiology is still not well defined. Genome sequence of C. jejuni revealed TAT pathway genes as well as several proteins that contain TAT pathway targeting motifs. The predicted Tat substrates are highly conserved among all sequenced C. jejuni strains. Phenotypic analyses revealed that the tatC knockout has defects in biofilm formation, motility, and flagellation, as well as an increased susceptibility to antimicrobials. Additionally, the tatC mutant was defective in survival under osmotic shock, oxidative, and nutrient stresses. Our results also indicated that tatC is essential for C. jejuni to sustain colonization in chickens. These findings suggest that the TAT pathway affects Campylobacter physiology and contributes to stress responses, allowing this fastidious pathogen to adapt to various environmental conditions.
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U2 - 10.1089/fpd.2009.0298
DO - 10.1089/fpd.2009.0298
M3 - Article
C2 - 19799526
AN - SCOPUS:70350116668
SN - 1535-3141
VL - 6
SP - 935
EP - 945
JO - Foodborne pathogens and disease
JF - Foodborne pathogens and disease
IS - 8
ER -