Viable but non-culturable(VBNC)bacteria after chlorination disinfection pose a considerable threat to the public health and environment.The current work aimed to uncover the stress adaptation mechanisms of VBNC Salmon...Viable but non-culturable(VBNC)bacteria after chlorination disinfection pose a considerable threat to the public health and environment.The current work aimed to uncover the stress adaptation mechanisms of VBNC Salmonella Enteritidis to sodium hypochlorite.In this study,we investigated the morphology,gene expressions and proteomic profile in VBNC S.Enteritidis.It demonstrated that 10^(9) cells/mL of bacteria could transition into the VBNC state after exposure to 50 mg/L chlorine for 2.5 h.The VBNC state cells exhibited cellular membrane impairment,decreased size,and intracellular ATP depletion compared to the culturable cells.In the VBNC state cells,there was a significant increase in intracellular reactive oxygen species(ROS)levels and NAD^(+)/NADH ratios.This observation suggested an imbalance in the intracellular redox status of the VBNC bacteria.Transcriptome and proteomic analysis revealed significant upregulation of the resistance-nodulation-division(RND)efflux systems(arcA,tolC,ramA),oxidative stress response genes(soxR,trxA,grxB),DNA repair genes(lexA,radA,mutH,mutL),and virulence factor genes(sseA,sseL,eutS,and eutE).Our findings indicated that it is important to formulate disinfection protocols that are specifically designed for food processing plants and healthcare facilities,focusing on implementing a more thorough disinfection method to effectively eradicate VBNC cells.展开更多
基金supported by the Natural Science Founding of Zhejiang(LZ24C200004)National Natural Science Founding of China(32302233)+4 种基金Key Research and Development Program of Zhejiang Province(2022C02049)Risk Assessment Program of Ministry of Agriculture and Rural Affairs(20244027)the Walmart Foundation(UA2020-152,UA2021-247)Zhejiang Provincial Department of Agriculture and Rural Affairs Project(2024SNJF044)Key Research and Development Program of Zhuji(2022J10)。
文摘Viable but non-culturable(VBNC)bacteria after chlorination disinfection pose a considerable threat to the public health and environment.The current work aimed to uncover the stress adaptation mechanisms of VBNC Salmonella Enteritidis to sodium hypochlorite.In this study,we investigated the morphology,gene expressions and proteomic profile in VBNC S.Enteritidis.It demonstrated that 10^(9) cells/mL of bacteria could transition into the VBNC state after exposure to 50 mg/L chlorine for 2.5 h.The VBNC state cells exhibited cellular membrane impairment,decreased size,and intracellular ATP depletion compared to the culturable cells.In the VBNC state cells,there was a significant increase in intracellular reactive oxygen species(ROS)levels and NAD^(+)/NADH ratios.This observation suggested an imbalance in the intracellular redox status of the VBNC bacteria.Transcriptome and proteomic analysis revealed significant upregulation of the resistance-nodulation-division(RND)efflux systems(arcA,tolC,ramA),oxidative stress response genes(soxR,trxA,grxB),DNA repair genes(lexA,radA,mutH,mutL),and virulence factor genes(sseA,sseL,eutS,and eutE).Our findings indicated that it is important to formulate disinfection protocols that are specifically designed for food processing plants and healthcare facilities,focusing on implementing a more thorough disinfection method to effectively eradicate VBNC cells.
