海洋低温几丁质酶菌株筛选、鉴定及酶谱分析

Screening,Identification and Zymogram Analysis of a Marine Cold-adapted Chitinase-producing Strain

以胶体几丁质为唯一碳源,从大连渤海湾的底泥样品中分离到1株高产低温几丁质酶的海洋细菌,命名为DL-06。由菌株的形态特征结合16SrDNA系统发育分析,初步确定该菌株属于交替假单胞菌(Pseudoalteromonas sp.DL-06)。该菌株经30h摇瓶发酵后测定粗酶液几丁质酶酶活为9.184U/mL,最适反应温度为15℃,60℃孵育1h仍保持50%以上的酶活性,表明该低温酶具有一定热稳定性。经SDSPAGE及酶谱分析,该菌株能够产生至少3种以上不同分子质量的几丁质酶组分。Pseudoalteromonas sp.DL-06产几丁质酶在低温下高活性与热稳定特点,使其具有潜在的工业应用价值。

Using colloidal chitin as the sole carbon source, a marine bacteria with high productivity of cold-adapted chitinase was obtained from samples collected in Bohai bay in Dalian city of Liaoning Province , China, named as DL-06. According to its physiological, biochemical characteristics and 16S rDNA sequence, it was identified as Pseudoalteromonas sp. DL-06. The chitinase activity was 9. 184 U/mL by 30 h shake-flask fermentation. The highest activity of chitinase was at 15 ℃, the chitinase still showed more than 50% of its highest activity at 60 ℃ after incubating for 1 h, which in- ferred its thermal stability. More than three different chitinases could be produced by the strain based on the analysis of SDS-PAGE and zymogram. Regarding its high activity at low temperature and ther- mal stability, the chitinase from Pseudoalteromonas sp. DL-06 has an industrial application potential.