保加利亚乳杆菌不同环境胁迫的交互保护作用及其基因表达分析  

Cross Protection of Lactobacillus delbrueckii subsp.Bulgaricus under Different Environmental Stresses and Analysis of Gene Expression

作　　者：张鑫 李晨[1,4] 张帅 王羽[1] 田洪涛[1,2,4] 王妙姝[3,4] Zhang Xin;Li Chen;Zhang Shuai;Wang Yu;Tian Hongtao;Wang Miaoshu(College of Food Science and Technology,Agricultural University of Hebei,Baoding 071000,Hebei;National Engineering Research Center for Agriculture in Northern Mountainous Areas,Baoding 071000,Hebei;Hebei New Hope Tianxiang Dairy Industry,Baoding 071000,Hebei;Hebei Technology Innovation Center of Probiotic Functional Dairy Product,Baoding 071000,Hebei)

机构地区：[1]河北农业大学食品科技学院,河北保定071000 [2]国家北方山区农业工程技术研究中心,河北保定071000 [3]河北新希望天香乳业有限公司,河北保定071000 [4]河北省益生功能性乳制品技术创新中心,河北保定071000

出　　处：《中国食品学报》2022年第9期24-35,共12页Journal of Chinese Institute Of Food Science and Technology

基　　金：国家自然科学基金项目(31301520);河北省农业科技成果转化项目(16822807D)。

摘　　要：保加利亚乳杆菌是发酵乳制品常用主要菌种,经常受到多种环境胁迫。为了深入揭示其抗逆保护机制,在确定保加利亚乳杆菌模式菌株ATCC 11842不同环境胁迫(酸、盐、胆盐、氧、冷)下的亚致死与最低致死条件的基础上,通过比较不同环境胁迫亚致死条件处理后的菌体细胞的存活率变化,研究菌体细胞在多重胁迫环境下的交互保护作用。根据前期ATCC 11842菌株在酸胁迫和酸冷胁迫条件下转录组学测序结果,从响应酸胁迫的基因中选取与糖代谢、氨基酸代谢、转运系统、分子伴侣、应激等相关11个基因,利用RT-qPCR技术分析11个基因在不同环境胁迫下转录水平的表达量变化。结果表明:ATCC 11842菌株经酸胁迫和氧胁迫亚致死条件(pH 4.8,40 min;15 mmol/L H_(2)O_(2),1 h)预处理后,均可显著提高最低致死条件下的存活率,在ATCC 11842菌株体内响应酸胁迫的11个基因中,有10个基因也响应其它不同环境胁迫,并探明这10个响应酸胁迫的基因(LDB_RS02110、LDB-RS00810、LDB_RS04920、LDB_RS05285、LDB_RS00230、LDB_RS06340、LDB_RS05615、LDB-RS01180、LDB_RS06995、LDB_RS03130)在不同环境胁迫下的表达变化。Lactobacillus bulgaricus is the main strain of fermented dairy products,but it is often subjected to various environmental stresses.For revealing the anti-stress protection mechanism,the Lactobacillus delbrueckii subsp.bulgaricus ATCC 11842 was used to determine the sublethal and minimum lethal conditions of bacterial cells under different environmental stresses(acid,salt,bile salt,oxygen,and cold).By comparing the survival rate of bacterial cells treated with sublethal conditions of different environmental stresses,the cross protective effects of bacterial cells under multiple stress environments were studied.According to the transcriptomics sequencing results of ATCC 11842 strain under acid stress and acid-cold stress,11 genes related to sugar metabolism,amino acid metabolism,transport system,molecular chaperone,and stress were selected,and the RT-qPCR technology was used to analyze the expression changes of these genes at the transcription level under different environmental stresses.The results show that:ATCC 11842 strain can significantly improve the survival rate under the minimum lethal conditions after pretreatment with acid stress and oxygen stress sublethal conditions(pH 4.8,40 min;15 mmol/L H_(2)O_(2),1 h).Among the 11 genes that respond to acid stress in the ATCC 11842 strain,10 genes were found to also respond to other different environmental stresses.The expression of LDB_RS02110,LDB-RS00810,LDB_RS04920,LDB_RS05285,LDB_RS00230,LDB_RS06340,LDB_RS05615,LDB-RS01180,LDB_RS06995 and LDB_RS03130 were significantly up-regulated and down-regulated.

关 键 词：保加利亚乳杆菌 不同环境胁迫 交互保护作用 转录水平 基因表达分析 

分 类 号：TS201.3[轻工技术与工程—食品科学]