新型产琼胶酶海洋细菌的筛选和鉴定

Screening and Identification of A Novel Marine Bacterium Producing Agarase

从大连沿海的50份石花菜中筛选出相对酶活较高的83株产琼胶酶菌株(酶活力测定采用3,5-二硝基水杨酸法),挑选琼胶酶活力最高的菌株并通过形态学特征、生理生化特征及16S r RNA基因序列分析研究其分类地位。结果表明,该菌株(暂命名为ZGR-26)为革兰氏阴性杆菌,与食琼胶弧菌(Vibrio agarivorans)序列同源性达到99%,两者生理生化特性基本相符,可初步确定为食琼胶弧菌(Vibrio agarivorans)。筛选得到了新型的产琼胶酶海洋细菌——食琼胶弧菌(Vibrio agarivorans),分泌琼胶酶活力较高(32.1 U/m L),为微生物降解法生产琼胶寡糖提供了新的出发菌株。

83 agarase-producing strain with high enzyme activity were screened from 50 samples of Gelidium in Dalian coast by DNS method.The morphology,physiological characteristics and 16SrRNA sequence of the strains were identified to characterize its classification status.The results showed that the strain （named as ZGR-26） was Gram negative bacilli,had 99％ homology and consistent physiological and biochemical characteristics with Vibrio agarivorans.The screened novel marine agarase-producing bacteria was identified as Vibrio agarivorans.The activity of producing agarase reached to 32.1 U/mL.It will provide a initial strain to agar-oligosaccharides manufacture by bio-degradation.