华癸中慢生根瘤菌多铜氧化酶基因mco的功能研究  

Function of multicopper oxidase gene mco in Mesorhizobium huakuii

作　　者：程国军[1] 邹倩 吴和涛 罗莎 CHENG Guojun;ZOU Qian;WU Hetao;LUO Sha(Hubei Provincial Engineering and Technology Research Center for Resources and Utilization of Microbiology,College of Life Sciences,South⁃Central University for Nationalities,Wuhan 430074,China)

机构地区：[1]中南民族大学生命科学学院微生物资源与利用湖北省工程技术研究中心

出　　处：《中南民族大学学报（自然科学版）》2020年第1期35-40,共6页Journal of South-Central University for Nationalities：Natural Science Edition

基　　金：国家自然科学基金资助项目(31772399);中央高校基本科研业务费专项资金资助项目(CZY18022)

摘　　要：通过基因同源重组技术,构建华癸中慢生根瘤菌mco基因突变株HKmco,并探究了mco基因突变对根瘤菌生长、抗氧化以及共生固氮的影响.结果表明:mco基因缺失不影响华癸中慢生根瘤菌的生长能力,突变株对无机过氧化物H2O2不敏感,但对有机氧化物氢过氧化枯烯(CUOOH)非常敏感.植物盆栽实验表明,突变株HKmco感染紫云英宿主能形成红色有效根瘤,但mco基因突变株Hkmco的根瘤中的类菌体形态发生了改变,固氮酶活降低了29.8%.表明根瘤菌mco基因在抗氧化和共生固氮方面发挥了重要作用.The mco mutant HKmco of M. huakuii was constructed by homologous recombination, and the effect of mco gene mutation on its growth, antioxidative and symbiotic nitrogen fixation function was further studied. The results showed that the mutation of mco gene had no effect on the growth ability of M. huakuii, and the mutant strain was not sensitive to the inorganic peroxide H2O2, but was significantly affected by the organic cumene hydroperoxide(CUOOH). Red effective nodules could be formed when mutant strain HKmco infected host Astragalus sinicus, but the morphology of bacteroids in nodules of mco gene mutant Hkmco changed. And nitrogenase activity reduced by 29.8%. It indicated that mco gene played an important role in the antioxidative and symbiotic nitrogen fixation function.

关 键 词：华癸中慢生根瘤菌 多铜氧化酶 mco基因 抗氧化 共生固氮 

分 类 号：Q939.11[生物学—微生物学]