常压室温等离子体快速诱变选育高产PHB菌株  

Screening of Highly Producing PHB Mutants by Atmospheric and Room Temperature Plasmas

作　　者：孔芳[1] 顾锐[1] 郭凤献 汪令翔 王幼平[2] 

机构地区：[1]安徽工程大学生物与化学工程学院,安徽芜湖241000 [2]扬州大学生物科学与技术学院,江苏扬州225009

出　　处：《环境科学与技术》2016年第8期51-57,共7页Environmental Science & Technology

基　　金：中国博士后科学基金(2013M541735);江苏省博士后基金(1301048B);国家级与安徽省大学生创新创业训练计划项目(201510363074;201510363063)

摘　　要：聚-β-羟基丁酸(PHB)具有生物可降解性,其分解产物可全部为生物利用,对环境无污染。该研究从污水处理厂的活性污泥中筛选产PHB的菌株,通过菌落形态观察、生理生化特征与16S r DNA系统树的构建、红外光谱分析、对菌株及采用氯仿乙醇法提取的发酵产物进行了鉴定。采用常压室温等离子体(ARTP)快速诱变产PHB野生菌株,结合苏丹黑染色及摇瓶复筛方法,筛选产PHB产量高且遗传特性稳定正向突变株。分离筛选到一株产PHB的原始菌株,被鉴定命名为Bacillus toyonensis GR-6,结果表明胞内聚合物PHB含量达43.04%(干细胞含量),产量为1.33 g/L。ARTP快速诱变的突变株PHB含量可达77.43%,产量为2.78 g/L,是原始菌株的2倍多,对突变株进行连续7代的传代发酵实验,各代表现出良好的遗传稳定性。突变株PHB产量与细胞干重比原始菌株显著提高,并具有良好的遗传稳定性,在微生物法生产可降解塑料的应用领域具有较大的潜在应用价值。Poly-β-hydroxybutyrate（PHB） possesses excellent biodegradability,whose decomposition products can be completely utilized and has no pollution to environment.Bacterium synthesizing PHB from activated sludge was screened and isolated,and the results showed that the strain was classified as Bacillus toyonensis based on standard morphological identification,physiological and biochemical tests,16 S r DNA sequence analysis and was named as GR-6.The fermented product from GR-6 was identified as PHB endocyte by infrared spectrum method,in which PHB yield and productivities were 43.04% dry cell weight（DCW） and 1.33 g/L,respectively.An atmospheric-and room temperature-plasma（ARTP）mutation system was employed to induce the mutation of highly producing PHB with Sudan black staining and shaking second screening.Compared with that of wild strain GR-6,a positive mutant obtained through ARTP was capable of producing PHB by 77.43% and the yield by 2.78 g/L,increased by more than twice.Further study showed that mutant possesses good genetic stability after 7 subcultures.The mutant is a potential candidate for future use in biodegradable plastics applications particularly in the microorganism fermenting production.

关 键 词：聚-β-羟基丁酸(PHB) 分离筛选 16SrDNA 红外光谱 常压室温等离子体诱变 

分 类 号：X172[环境科学与工程—环境科学]