Veterinary Microbiology and Preventive Medicine
Journal or Book Title
Applied and Environmental Microbiology
Campylobacter jejuni is a leading cause of foodborne illnesses worldwide. As a microaerophilic organism, C. jejuni must be able to defend against oxidative stress encountered both in the host and in the environment. How Campylobacter utilizes a mutation-based mechanism for adaptation to oxidative stress is still unknown. Here we present a previously undescribed phenotypic and genetic mechanism that promotes the emergence of oxidative stress resistant mutants. Specifically, we showed that a naturally occurring mutator phenotype, resulting from a loss of function mutation in the DNA repair enzyme MutY, increased oxidative stress resistance (OXR) in C. jejuni. We further demonstrated that MutY malfunction didn't directly contribute to the OXR phenotype, but increased the spontaneous mutation rate in the peroxide regulator gene perR, which functions as a repressor for multiple genes involved in oxidative stress resistance. Mutations in PerR resulted in loss of its DNA binding function and derepression of PerR-controlled oxidative stress defense genes, thereby conferring an OXR phenotype and facilitating Campylobacter survival under oxidative stress. These findings reveal a new mechanism that promotes the emergence of spontaneous OXR mutants in bacterial organisms.
American Society for Microbiology
Dai, Lei; Sahin, Orhan; Tang, Yizhi; and Zhang, Qijing, "A mutator phenotype promoting the emergence of spontaneous oxidative stress-resistant mutants in Campylobacter jejuni" (2017). Veterinary Microbiology and Preventive Medicine Publications. 181.
Genetics and Genomics Commons, Veterinary Microbiology and Immunobiology Commons, Veterinary Pathology and Pathobiology Commons, Veterinary Preventive Medicine, Epidemiology, and Public Health Commons