Nucleotide sequence of alkalophilic Bacillus oligo-1,6-glucosidase gene and the properties of the gene product by Escherichia coli HB 101.

Abstract

The nucleotide sequence of alkalophilic Bacillus oligo-1, 6-glucosidase gene was determined . The coding sequence on a 3.1 kb DNA fragment in pMC21 showed an open reading frame of 1527 by encoding 509 amino acids. The amino acid sequence from position 2 to 11 corresponds exactly to the NH2-terminal sequence of the purified enzyme protein from strain F5. The molecular weight (60, 142) of the protein derived from 1524 by open reading frame coincided with the molecular weight (60, 000) of the parent strain. On the other hand, the molecular weight of purified oligo-1, 6-glucosidase produced by E. coli HB101 carrying plasmid pMC21 showed 65, 000 by SDS-PAGE. The enzymatic properties, i. e., pH and temperature optima, pH and thermal stabilities, and substrate specificities, were almost the same as those obtained from an alkalophilic Bacillus sp. (strain F5).