乳酸乳球菌Q13细菌素对耐甲氧西林金黄色葡萄球菌的抑菌机理  

Antibacterial Mechanism of Bacteriocin of Lactococcus lactis Q13 against Methicillin-Resistant Staphylococcus aureus

作　　者：刘爽 王金丽 梁安健 杨洋洋 朱成林 唐俊妮[1] LIU Shuang;WANG Jinli;LIANG Anjian;YANG Yangyang;ZHU Chenglin;TANG Junni(College of Pharmacy and Food Science,Southwest Minzu University,Chengdu 610225,China)

机构地区：[1]西南民族大学药学与食品学院,四川成都610225

出　　处：《食品科学》2025年第9期30-38,共9页Food Science

基　　金：四川省自然科学基金面上项目(2024NSFSC0364);西南民族大学中央高校基本科研业务费专项资金项目(ZYN2025119)。

摘　　要：为探究乳酸乳球菌Q13所产细菌素对耐甲氧西林金黄色葡萄球菌(methicillin-resistant Staphylococcus aureus,MRSA)的抑菌机制,利用乳酸乳球菌Q13细菌素对MRSA进行处理,对最小抑菌浓度(minimum inhibitory concentration,MIC)、生长情况、生物被膜形成、DNA复制情况等进行分析,并利用实时定量聚合酶链式反应研究细菌素对MRSA被膜形成基因、毒力基因、与DNA复制有关基因表达的影响。结果表明Q13细菌素对MRSA的MIC为0.78 mg/mL,能够明显抑制MRSA生长,扫描电镜观察发现Q13细菌素可破坏MRSA细胞膜,导致细胞内容物流出;MRSA细胞在不同浓度Q13细菌素处理下核酸和蛋白泄漏量均明显提高,当Q13细菌素质量浓度为1 MIC时,核酸和蛋白泄漏量分别提高了614.71%、1173.91%;Q13细菌素对MRSA生物被膜有抑制和清除作用,当Q13细菌素质量浓度为1 MIC时,对被膜抑制率与清除率分别达到95.03%、56.14%;与抗生素药物复合使用时,抗生素对Q13细菌素既有协同作用又有拮抗作用;经Q13细菌素处理的MRSA细胞DNA含量有所减少;Q13细菌素处理可引起耐药基因、被膜形成相关基因、毒力基因、与DNA复制有关基因表达下调。综上,Q13细菌素将来可作为天然防腐剂应用到食品工业。The antibacterial mechanism of bacteriocin produced by Lactococcus lactis Q13 against methicillin-resistant Staphylococcus aureus(MRSA)was investigated in this study.The minimum inhibitory concentration(MIC)of the bacteriocin was tested,and its effects on bacterial growth,biofilm formation and DNA replication were evaluated.Meanwhile,quantitative polymerase chain reaction(qPCR)was used to study the effect of the bacteriocin on the expression of biofilm formation-related genes,virulence genes and genes related to DNA replication in MRSA.The results showed that bacteriocin Q13 could inhibit the growth of MRSA,with an MIC of 0.78 mg/mL.Scanning electron microscopy showed that bacteriocin Q13 could destroy the cell membrane of MRSA,leading to the leakage of intracellular contents.The leakage of nucleic acid and protein from MRSA cells increased obviously at all concentrations of bacteriocin Q13.At 1 MIC concentration,the leakage of nucleic acid and protein increased by 614.71%and 1173.91%,respectively.The bacteriocin could inhibit and eradicate the biofilm of MRSA.At 1 MIC concentration,the inhibition rate and eradication rate of MRSA biofilm were 95.03%and 56.14%,respectively.Both synergistic and antagonistic effects were observed between antibiotics and bacteriocin Q13.The DNA content of MRSA cells decreased after treatment with the bacteriocin,and the expression of drug resistance genes,membrane formation-related genes,virulence genes and DNA replication-related genes was downregulated.This study showed the potential of bacteriocin Q13 as a natural preservative in the food industry.

关 键 词：乳酸乳球菌 细菌素 耐甲氧西林金黄色葡萄球菌 抑菌机制 

分 类 号：TS252.1[轻工技术与工程—农产品加工及贮藏工程]