To obtain the subject new enzyme, a heat-resistant phosphorylase derived from Bacillus stearothermophilus, useful for antimicrobial agents for medical use, antitumor agents, therapeutic agents for cardiopathy, and for producing α-glucan and the substrates for synthesizing α-glucan.
This enzyme is a new heat-resistant phosphorylase having the following characteristics: having variation(s) due to the deletion, substitution or addition of at least one amino acid in the amino acid sequence ranging from the 1st Met to the 798th Met in the sequence table shown by the formula; forming glucose-1-phosphate and α-1,4-glucan through acting on starch; optimum temperature is 50°C; resistant to heat even at 60°C; and stable at pH6.5-11. This enzyme is useful, for antimicrobial agents for medical use, antitumor agents (platinum complex), therapeutic agents for cardiopathy (amine salt), and for producing glucose-1-phosphate as a substrate for synthesizing α-glucan. This new enzyme is obtained by subjecting the chromosome DNA of Bacillus stearothermophilus TRBE14 strain to PCR using a primer followed by expressing the resultant gene.
TAKABA TAKESHI
OKADA SHIGETAKA
IMANAKA TADAYUKI