ABSTRACT
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% with those of the same genus bacteria Pseudoalteromonas citrea and Pseudoalteromonas 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 celX gene exhibits 95% sequence identity with endoglucanase CelG from Pseudoalteromonas haloplanktis. There are two modules in the deduced amino acids sequence, 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 domain by a short linker. The optimal temperature of CelX is 40 degrees C and the optimal pH was between 6 and 7.
Subject(s)
Amino Acid Sequence , Bacterial Proteins , Genetics , Cellulase , Genetics , Cloning, Molecular , Gene Expression Regulation, Enzymologic , Molecular Sequence Data , Pseudoalteromonas , Genetics , Sequence AlignmentABSTRACT
Thermophilic bacteria strain YBJ-1 was isolated from hot spring samples collected from Yangbajing, Tibet. The 16sr DNA sequence of YBJ-1 (1511bp in length) shares 98% identity with that of Thermus scotoductus strain ITI-252T. The full-length ORF of amylase gene of YBJ-1 (amyT) was amplified by PCR technique and cloned into T-vector. The complete sequence of amyT is 1767bp in length, coding for 588 amino acids. The deduced amino acids share 99% similarity with alpha-cyclodextrinse of Bacillus sterothermophilus, 96% with maltogenic amylse of Thermus. sp IM6501, and 81% with neopullulanase of Bacillus sterothermophlus.