ClpB enhances thermotolerance in through protein disaggregation independent of DnaK.

is a leading cause of foodborne infections worldwide and primarily transmitted to humans through the consumption of contaminated poultry meat. To enhance -associated food safety, it is critical to understand how survives during the thermal processing of poultry products. In this study, we monitored the survival of 86 . strains during heat treatment and observed that some strains exhibited elevated heat tolerance. Notably, multilocus sequence typing clonal complex (CC)-443 and CC-607 were dominant among heat-tolerant strains, while the CC-21 strains were mostly heat-sensitive, indicating phylogenetic association with thermotolerance. We also investigated the function of heat shock chaperones in the thermotolerance of . Among several knockout mutants of heat shock chaperones, a mutant lacking exhibited significantly lower survival than the wild type under heat treatment. Moreover, we observed a significantly higher accumulation of protein aggregates in the absence of , demonstrating that ClpB functions as a disaggregase during heat exposure. Additionally, ClpB from the heat-tolerant CC-443 group possessed distinct amino acid substitutions in the functional nucleotide-binding domain compared to ClpB in other CC groups. Interestingly, despite the well-known interaction of these proteins in many other bacteria, a two-hybrid assay demonstrated that ClpB of does not bind to DnaK, suggesting that may have a distinct mechanism for protein disaggregation and stress tolerance. Our findings demonstrate that ClpB plays a crucial role in the thermotolerance of through unique protein disaggregation mechanisms during poultry processing.IMPORTANCEThis study unveils a distinctive mechanism of thermotolerance involving protein disaggregation in , a major foodborne pathogen. Understanding 's ability to withstand heat stress is crucial for comprehending the occurrence of infections resulting from the consumption of contaminated poultry meat. Our research elucidates the roles of heat shock proteins, particularly ClpB, in the thermotolerance of . These findings significantly contribute to our fundamental understanding of bacterial physiology related to stress tolerance, which has important implications for public health and food safety.