莫能菌素高产菌的航天诱变与基因工程复合选育  

Cascading Strain Breeding of High Monensin Producing Strain with Space Mutation and Genetic Engineering

作　　者：黄子瑄 张善飞 刘旻炜 孙付保[1,2] HUANG Zixuan;ZHANG Shanfei;LIU Minwei;SUN Fubao(Key Laboratory of Industrial Biotechnology,Ministry of Education,Jiangnan University,Wuxi 214122,China;School of Biotechnology,Jiangnan University,Wuxi 214122,China)

机构地区：[1]江南大学工业生物技术教育部重点实验室,江苏无锡214122 [2]江南大学生物工程学院,江苏无锡214122

出　　处：《食品与生物技术学报》2024年第11期124-132,共9页Journal of Food Science and Biotechnology

基　　金：国家自然科学基金面上项目(22278189)。

摘　　要：莫能菌素(monensin)是肉桂地链霉菌(Streptomyces cinnamonensis,S.cinnamonensis)发酵产生的聚醚类抗生素,因其不易产生耐药性、绿色安全等优势在农业、畜牧业等领域广泛应用。作者对肉桂地链霉菌2110的航天诱变和基因工程育种开展系统研究,以期提高其产莫能菌素的发酵性能。通过抗性平板结合微孔板培养体系筛选航天诱变的突变体,最终获得一株遗传稳定性良好的高产突变菌S.cinnamonensis G43,发酵罐效价比原始菌2110提高16.5%。将突变菌进行莫能菌素合成调控基因的单独/双串联过表达,通过整合过表达调控基因monRI、dasR得到工程菌G43-dasR-monRI,该菌在5 L发酵罐中的效价达11.3 kU/mL,较原始菌2110提高33.1%。结果表明,航天诱变与基因工程育种相结合能有效用于莫能菌素高产菌的选育,可为其他聚醚类抗生素生产菌的菌种改良提供借鉴。Monensin is a kind of polyether antibiotic produced by Streptomyces cinnamonensis(S.cinnamonensis),which is widely used in fields such as agriculture and animal husbandry with the advantages of low tendency to resistance and environmentally friendly properties.The author systematically investigated the fermentation performance improvement of S.cinnamonensis srain 2110 by combination of space mutation and genetic engineering breeding.High-yielding mutants from space mutation were selected through resistance screening combined with a microplate culture system.Results showed that a highly monensin producing mutant S.cinnamonensis G43(G43)was obtained with a relatively good genetic stability,in which its monensin titer increased by 16.5%as compared to the parental strain.Subsequently,independent and tandem overexpression of monensin synthesis regulatory genes were conducted around the mutant strain.With successful integration of regulatory genes monRI and dasR,the engineering strain G43-dasR-monRI was finally obtained,and its monensin titer reached 11.3 kU/mL in a 5 L bio-fermenter,representing a 33.1%increase compared to the parental strain 2110.The results demonstrated that the combination of space mutation and genetic engineering breeding can be effectively applied to select high-yield strains for monensin production and may provide a reference for strain improvement of other polyether antibiotic-producing microorganisms.

关 键 词：莫能菌素 航天诱变 途径特异性调控 基因整合 过表达 肉桂地链霉菌 

分 类 号：S85[农业科学—兽医学]