科微学术
微生物学通报
2025年5月6日 周二
YANG Qingshan
1 Guangxi Research Center for Microbial and Enzyme Engineering Technology, College of Life Science and Technology, Guangxi University, Nanning 530004, Guangxi, China;HUANG Luodong
1 Guangxi Research Center for Microbial and Enzyme Engineering Technology, College of Life Science and Technology, Guangxi University, Nanning 530004, Guangxi, China;WU Yiting
1 Guangxi Research Center for Microbial and Enzyme Engineering Technology, College of Life Science and Technology, Guangxi University, Nanning 530004, Guangxi, China;ZHANG Xi
1 Guangxi Research Center for Microbial and Enzyme Engineering Technology, College of Life Science and Technology, Guangxi University, Nanning 530004, Guangxi, China;SHEN Peihong
1 Guangxi Research Center for Microbial and Enzyme Engineering Technology, College of Life Science and Technology, Guangxi University, Nanning 530004, Guangxi, China;【背景】甲基营养菌(Methylobacterium)是一类能够以单碳或非C-C键低碳化合物(如甲烷、甲醇、甲醛等)为底物生长，并可生产多种代谢产物如氨基酸、工业酶和辅助因子、多羟基烷酸酯(polyhydroxyalkanoates，PHA)、多糖和类胡萝卜素等的革兰氏阴性细菌。【目的】通过突变甲基营养菌MB200的mutS基因，在胁迫条件下定向诱导，以获得可以耐受高浓度甲醇和甲醛的生产菌株。【方法】利用三亲本结合构建mutS基因缺失的高突变菌株MB200sTB，逐步提升培养液中甲醇、甲醛的浓度进行定向诱导突变，对获得的高耐受性突变株进行回补，分析菌株的生长情况。【结果】构建了mutS基因的缺失突变体MB200sTB，并且得到了高耐受甲醇和甲醛的菌株MB200sHBc和MB200sHBq。MB200sHBc与野生株MB200相比其甲醇耐受性得到了极显著的提高，甲醇耐受浓度从8 g/L提升到44 g/L，但生长量不受影响。MB200sHBq在以甲醛为0.45 g/L的碳源条件下，生长量相较于野生型MB200提高了1.69倍。【结论】通过定向诱导缺失mutS基因的突变体，可获得具有生产应用潜力的高耐甲醇菌株。
[background] The Gram-negative Methylobacterium has the ability to grow in the low-carbon compound (such as methane, methanol, formaldehyde and so on) substrate with one carbon atom or no C−C bond, and synthesizes various metabolites such as amino acids, industrial enzymes, cofactors, polyhydroxyalkanoates (PHAs), polysaccharides, and carotenoids. [Objective] In this study, mutation of mutS gene in Methylobacterium sp. MB200 was performed, and targeted induction was conducted with stresses to yield mutant strains that can tolerate high concentration of methanol or formaldehyde. [Methods] The mutS deletion strain MB200sTB was constructed by triparental mating, and the concentration of methanol and formaldehyde in the culture medium was gradually increased to induce targeted mutations. Electrotransformation was used to yield complementary transformants. [Results] MB200sTB with mutS deletion was successfully constructed, and the methanol-tolerant MB200sHBc and formaldehyde-tolerant MB200sHBq were obtained. The methanol tolerance of MB200sHBc was greatly improved compared with that of the wild strain MB200. To be specific, the tolerant methanol concentration raised from 8 g/L to 44 g/L and the growth kept unchanged. In the presence of 0.45g/L formaldehyde as carbon source, the growth of MB200sHBq was 1.69 folds higher than that of MB200. [Conclusion] Through targeted induction of mutS deletion mutants, strains with high methanol tolerance and potential application prospect in production can be obtained.
杨青山,黄罗冬,吴宜婷,张茜,申佩弘. 甲基营养菌MB200中mutS的缺失及高浓度甲醇和甲醛诱变[J]. 微生物学通报, 2022, 49(7): 2730-2740
复制
