农用抗生素高产菌株的筛选分离及诱变育种

Screening, isolation and mutation breeding of strain with high yield agricultural antibiotic

该实验分离得到4株产农用抗生素菌株,编号1~#~4~#。以厚垣镰孢霉(Fusarium chlamydosporum)、枯草芽孢杆菌(Bacillus subtilis)、大肠杆菌(Escherichia coli)、金黄色葡萄球菌(Staphylococcus aureus)作为指示菌,测定其发酵液的抑菌活性,并对抑菌活性菌株进行诱变育种。结果表明,菌株1~#对枯草芽孢杆菌(B.subtilis)和金黄色葡萄球菌(S.aureus)抑菌圈直径>10 mm,抑菌活性较好。采用紫外诱变、重金属激活沉默基因复活诱变两种方法诱变菌株1~#后,对厚垣镰孢霉、枯草芽孢杆菌、大肠杆菌、金黄色葡萄球菌抑菌作用分别增加了25.68%、32.11%、34.85%、28.28%。形态学观察及生理生化实验结果初步鉴定菌株1~#为链霉菌属(Streptomyces sp.)。

Four agricultural antibiotic-producing strains were screened and numbered as 1#-4#.Using Fusarium chlamydosporum,Bacillus subtilis,Escherichia coli,Staphylococcus aureus as indicator microbes,the antibacterial activities of fermentation broth were determined and strains with antibacterial activity were mutated breeding.The results showed that inhibitory effects of strain 1#on B.subtilis and S.aureus were better,and the inhibitory zone diameters were more than 10 mm.Inhibitory effects of strain 1#mutated by UV-mutation and heavy metal activating silent genes on F.chlamydosporum,B.subtilis,E.coli and S.aureus increased by 25.68%,32.11%,34.85%and 28.28%,respectively.The strain 1#was preliminarily identified as Streptomyces sp.by morphological observation and physiological and biochemical experiments.