一株降解淀粉填充聚乙烯放线菌的筛选以及诱变选育

Isolation and Complex Mutagenesis of an Actinomycetes with Degraded Starch/Polyethylene Powder

目前对聚乙烯降解菌的研究主要集中在细菌和真菌中,放线菌作为聚乙烯降解菌株还鲜有报道.利用添加改良淀粉聚乙烯粉末为唯一碳源和能源的无碳源培养基,从土壤中分离筛选得到一株可以降解淀粉聚乙烯的降解菌LBX-2,通过形态学观察生理生化反应,结合16Sr DNA序列进行分类鉴定,菌株LBX-2与Streptomyces albogriseolus的亲缘关系最近,形态学观察和生理生化指标也与之相符,初步鉴定为白浅灰链霉菌.以筛选得到的降解菌LBX-2作为出发菌株,采用吖啶橙-紫外线复合诱变的方法进行诱变选育,吖啶橙最佳诱变剂量为1×10^(-2)g/m L,紫外线最佳诱变持续时间为50 s,诱变株较之原始菌株降解能力提高了41.80%,是一株具有研究和应用潜力的降解淀粉聚乙烯的菌株.

At present,the research of polyethylene degradation bacteria mainly focused on the bacteria and fungi,while actinomycetes as degradation strains are rarely reported. In this article,modified Starch / polyethylene powder as sole carbon and energy source were employed. A strain LBX-2 which can degrade starch / polyethylene was isolated from soil and identified by the phenotypic to abtain,physiological and biochemical characteristics. With 16 Sr DNA gene cloned sequence,the isolated strain LBX-2 was identified to be closely related to Streptomyces albogriseolus. Phenotypic,physiological and biochemical characteristics are the same with Streptomyces albogriseolus. With LBX-2 as the starting stain by using acridine orange and UV irradiation treatment,the best mutagenic effect was proved through experiment 1 × 10- 2g / m L after mutated with acridine orange and 50 s ultraviolet radiation. The isolated strains named Streptomyces albogriseolus can degrade starch / polyethylene powder after complex mutation with acridine orange and ultraviolet radiation,and the degradation capacity can be improved 41. 80% higher than that of the original strain. Thus,it is a valuable and potential strain in the research of degradation of Starch / polyethylene powder.