摘要
为了探究可以引发呕吐型食物中毒的蜡样芽孢杆菌呕吐毒素的合成机制,本研究通过同源重组对潜在调控基因yjbK进行敲除,发现yjbK在蜡样芽孢杆菌呕吐毒素合成中起正调控作用。通过生物信息学分析,确定了YjbK的潜在磷酸水解酶活性及ExExK关键位点。随后,构建了YjbK的点突变表达与回补菌株,明确了E6和E8位点的突变显著降低了磷酸水解酶活性及呕吐毒素的产量,从而证实了磷酸水解酶活性在蜡样芽孢杆菌呕吐毒素合成进程中发挥了正调控作用。本研究结果可为揭示呕吐毒素合成的分子调控机制提供新的理论依据。
Our aim was to explore the synthesis mechanism of cereulide in Bacillus cereus,causing vomiting-type food poisoning.In this study,the potential regulatory gene yjbK was knocked out by homologous recombination,revealing that yjbK positively regulated the synthesis of cereulide in B.cereus.Through bioinformatics analysis,the potential phosphohydrolase activity of YjbK and the key sites of ExExK were determined.Subsequently,point mutant expression and complementary strains of YjbK were constructed,and it was clarified that mutations at sites E6 and E8 significantly reduced the activity of phosphohydrolase and the yield of cereulide,thereby confirming that phosphohydrolase activity positively regulated the synthesis of cereulide in B.cereus.This study provides a new theoretical basis for understanding the molecular regulatory mechanism of cereulide synthesis.
作者
梁欣敏
李佳珣
李阳福
秦科元
李湘
张菊梅
王涓
吴清平
丁郁
LIANG Xinmin;LI Jiaxun;LI Yangfu;QIN Keyuan;LI Xiang;ZHANG Jumei;WANG Juan;WU Qingping;DING Yu(Department of Food Science and Engineering,Jinan University,Guangzhou 510632,China;National Health Commission Science and Technology Innovation Platform for Nutrition and Safety of Microbial Food,Guangdong Provincial Key Laboratory of Microbial Safety and Health,State Key Laboratory of Applied Microbiology Southern China,Institute of Microbiology,Guangdong Academy of Sciences,Guangzhou 510070,China;School of Biology and Biological Engineering,South China University of Technology,Guangzhou 510006,China;College of Food Science,South China Agricultural University,Guangzhou 510642,China)
出处
《食品科学》
北大核心
2025年第7期125-134,共10页
Food Science
基金
国家自然科学基金面上项目(32272424)
广东省基础与应用基础研究重大项目(2020B0301030005)
“十四五”国家重点研发计划重点专项(2022YFF1100700)。
