抗噬菌体L-苏氨酸工程菌的选育及机理分析  

Breeding and mechanism analysis of phage resistant L-threonine engineering bacteria

作　　者：王强[1] 杨立鹏 魏爱英 孟刚 WANG Qiang;YANG Li-peng;WEI Ai-ying;MENG Gang

机构地区：[1]宁夏医科大学医学科学技术研究中心,宁夏银川750001 [2]宁夏伊品生物科技股份有限公司,宁夏银川750100

出　　处：《饲料研究》2022年第9期100-105,共6页Feed Research

摘　　要：试验通过常压室温等离子体诱变苏氨酸生产菌,筛选获得具有噬菌体抗性的苏氨酸基因工程菌株。从苏氨酸发酵染噬菌体发酵液中分离得到混合噬菌体(P-1)。以P-1为筛选因子,通过常压室温等离子体诱变苏氨酸生产菌YPT、抗性初筛、溶原性验证、噬菌体抗性遗传稳定性验证、发酵罐产酸等验证。结果显示:通过筛选得到1株对P-1具有稳定抗性的苏氨酸生产菌株,命名为YPT-1。在分子水平上对突变株YPT-1抗噬菌体的机制做初步研究。采用CRISPR技术进行敲除验证,证实fhuA基因的缺失可致使菌株获得噬菌体抗性。研究表明,经过初步产酸验证,此菌株产酸指标与对照株(诱变出发菌YPT)相比未下降,且产酸稳定,具有较好的工业化应用价值。The threonine gene-engineered strains with the resistance to pha-ges were screened by atmospheric room temperature plasma(ARTP).The mixed phage(P-1)was isolated from the broth of threonine fermentation.P-1 was used as screening factor to mutate threonine producing strain YPT by atmospheric plasma at room temperature,preliminary screening of resistance,lysogenicity verification,genetic stability verification of phage resistance and acid production verification in fermentation tank.The results showed that a threonine producing strain with stable resistance to P-1 was obtained,which named YPT-1.The mechanism of the strain YPT-1 against phage was investigated based on molecular level.The knockout of fhuA gene was carried out by CRISPR,which indicated that the deletion of fhuA could lead to the achievement of phages resistance.The study indicates that compared with the control strain(YPT),the acid production index of the strain doesn't decrease.and the acid production is stable,which has good industrial application value.

关 键 词：L-苏氨酸 大肠杆菌 ARTP诱变 筛选 FHUA 

分 类 号：S816[农业科学—饲料科学]