海洋细菌Thalassomonas sp.LD5中新型褐藻胶裂解酶TsAly7C的研究

Study on the new alginate lyase TsAly7C from marine bacterium Thalassomonas sp.LD5

目的对来源于Thalassomonas sp.LD5的褐藻胶裂解酶TsAly7C进行研究,以期获得具有优良性质的褐藻胶裂解酶,适应工业需求。方法在生物信息学分析的基础上,对TsAly7C进行了重组表达和酶学性质研究。结果通过生物信息学分析,TsAly7C属于PL7家族的第一亚家族。对重组TsAly7C(rTsAly7C)酶学性质进行分析,rTsAly7C的最适温度是30℃,最适pH为8.0(Na_(2)HPO_(4)-NaH_(2)PO_(4)缓冲液),在底物中添加300 mmol/L NaCl时降解能力最强。rTsAly7C的pH稳定性和温度稳定性较好,在0~30℃保存1 h仍保有80%以上的酶活,是1种适低温性褐藻胶裂解酶。Cu^(2+)、Co^(2+)、Zn^(2+)、Ni^(2+)和十二烷基硫酸钠(SDS)对rTsAly7C的酶活有明显的抑制作用。rTsAly7C是1种双功能褐藻胶裂解酶,以内切形式裂解褐藻胶产生不饱和二糖和单糖。

Objective Through the study of alginate lyase TsAly7C from Thalassomonas sp.LD5,it was expected to obtain alginate lyase with excellent properties to meet the industrial demand.Methods On the basis of bioinformatics analysis,the cloning,recombinant expression and enzymatic properties of TsAly7C were studied.Results Through bioinformatics analysis,TsAly7C belongs to the first subfamily of PL7.The optimal temperature of rTsAly7C was 30℃,and the optimal pH was 8.0 in Na_(2)HPO_(4)-NaH_(2)PO_(4) buffer.rTsAly7C exhibited the maximum activity in the presence of 300 mmol/L NaCl.rTsAly7C retained more than 80%of the initial enzymatic activity after stored at 0−30℃for 1 h.Cu^(2+),Co^(2+),Zn^(2+),Ni^(2+)and SDS had a significant inhibiting effect on the enzyme activity of rTsAly7C.rTsAly7C was a bifunctional alginate lyase,which cleaved alginate in an endo-type to produce unsaturated disaccharides and monosaccharides.