Bacillus subtilis NX-2聚谷氨酸合成酶基因pgsBCA的克隆及生物信息学分析

摘要

The pgsBCA genes, encoding a poly-y-glutamic acid ( y-PGA) synthesis system of B. Subtilis NX-2, were cloned and sequenced. The physical and chemical properties, transmembrane region, signal peptide, cellular localization of PgsB, PgsC, and PgsA proteins were analyzed and predicted by using bioinformatics methods. Results showed that the essential ATP hydrolysis was mainly catalyzed by the action of PgsB protein, without transmembrane regions. PgsC was hydrophobic and membrane-bound protein containing four transmembrane regions. The pgsC gene was the most conservative gene of pgsBCA genes. PgsA was hydrophilic and stable protein containing one transmembrane domain near its N terminus , which seemed likely for the elongation of y-PGA. This study was helpful for explaining functions of the components PgsB, PgsC and PgsA of y-PGA synthesis system.%克隆Bacillus subtilis NX-2中的聚谷氨酸合成酶基因pgsBCA并进行测序.应用生物信息学分析方法和工具对PgsB、PgsC、PgsA蛋白质的理化性质、跨膜区域、信号肤、细胞定位等进行分析和预测,并探讨它们的作用方式.结果表明:PgsB蛋白不含有跨膜区,它与ATP结合并催化ATP的水解,为PGA合成提供能量;PgsC蛋白保守性最高,其含有4个跨膜区域,是疏水性膜结合蛋白;PgsA为亲水性稳定蛋白,在N端存在1个跨膜区域.