摘要
从深海样品ES0 10 9中分离到一株具有高内切葡聚糖酶活力的细菌DY3 ,16SrDNA序列分析表明该菌与交替假单胞菌属 (Pseudoalteromonassp .)的Pseudoalteromonascitrea和Pseudoalteromonaselyakovii的同源性为 99%。PCR扩增DY3的内切葡聚糖酶基因celX全长 14 79bp ,编码一个 492AA的蛋白质。酶的氨基酸序列分析表明CelX与Pseudoalteromonashaloplanktis的内切葡聚糖酶CelG有 95%的相似性 ,包括一个糖基水解酶家族 5的催化结构域 ,一个连接序列和位于C端的的CBM5结构域。对酶性质的初步研究发现 ,CelX的最适温度为 40℃ ,酶的最适pH在 6～
A bacteria strain DY3 with high endoglucanse activity was isolated from deep sea sediment sample ES0109.The 16S rDNA sequence of DY3 exhibits identity of 99% wi t h those of the same genus bacteria Pseudoalteromonas citrea and Pseudoalte romonas elyakovii. The celX gene of DY3 obtained by PCR method is 1479bp in length and encodes a protein of 492 amino acids. The protein encoded by ce lX gene exhibits 95% sequence identity with endoglucanase CelG from Pseudoa lteromonas haloplanktis. There are two modules in the deduced amino acids sequ ence, a catalytic domain of glycosyl hydrolases family 5 at the N terminal and a carbohydrate binding domain at the C terminal which was linked to catalytic dom ain by a short linker. The optimal temperature of CelX is 40℃ and the optimal p H was between 6 and 7.
出处
《生物工程学报》
CAS
CSCD
北大核心
2004年第2期233-237,共5页
Chinese Journal of Biotechnology
基金
国家大洋协会项目 (No .4 2 4 )~~
