ε-聚赖氨酸发酵过程污染微生物的分离与鉴定

Isolation and identification of contamination microorganisms in ε-poly-L-lysine fermentation process

摘要:

【目的】研究ε-聚赖氨酸发酵过程中污染微生物的种类。【方法】采用稀释涂布法、划线法、环境胁迫法和液体营养富集法等对污染样本进行微生物的分离与纯化，通过菌落形态和显微观察，再结合16S rRNA基因序列分析，确定分离菌株的系统发育地位，并对分离菌株的ε-聚赖氨酸耐受性进行考察。【结果】液体营养富集法实现了污染微生物的分离，通过16S rRNA基因序列分析鉴定其为一株Acinetobacter bereziniae，并证实该菌能在高浓度ε-聚赖氨酸条件下生长。【结论】Acinetobacter bereziniae是ε-聚赖氨酸发酵过程中的主要污染微生物，这为后期发酵污染防治提供了一定的指导作用。

Abstract:

[Objective] To solve the problem of contamination during ε-poly-L-lysine (ε-PL) fermentation, contamination microorganisms were screened and identified in this study. [Methods] Many strategies, like dilution coated plate, streak plate method, environmental stress method and liquid nutrient enrichment method, were performed to screen microorganisms from contaminated sample. Then the phylogenetic position of the isolate was determined through colony and microscopic morphology observation and 16S rRNA gene sequence analysis. Subsequently, the ε-PL tolerance of the isolate had evaluated. [Results] Contamination microorganisms were screened using liquid nutrient enrichment method isolated and identified as Acinetobacter bereziniae by 16S rRNA gene sequence analysis. Meanwhile, this isolate could tolerant high concentration of ε-PL. [Conclusion] Acinetobacter bereziniae was identified as the dominate contamination microorganism in ε-PL fermentation. And this find is helpful for the treatment of contamination microorganism in the process of ε-PL fermentation.