ISOLATION OF SOIL STRAINS PRODUCING NEW CEPHALOSPORIN ACYLASES

Cephalosporin acylase is an industrially important enzyme which converts cephalosporins into 7-amino cephalosporanic acid (7-ACA), the starting material for most of clinically used cephalosporin derivatives. We surveyed soil strains for their glutaryl 7-ACA and cephalosporin C acylase activities. We obtained two new glutaryl 7-ACA acylase producers, Pseudomonas sp. A14 and Bacillus laterosporus J1 and two new cephalosporin C acylase producers, Pseudomonas sp. N176 and V22. Substrate profiles of A14 and J1 glutaryl 7-ACA acylases were quite different from that of the known glutaryl 7-ACA acylase GK16. While the deacylation rate of succinyl 7-ACA and adipyl 7-ACA by GK16 acylase was much lower than that of glutaryl 7-ACA, A14 acylase deacylated succinyl 7-ACA 13-fold faster than glutaryl 7-ACA and J1 acylase deacylated adipyl 7-ACA at a rate comparable to that for glutaryl 7-ACA. Meanwhile, cephalosporin C acylase producers N176 and V22 were shown to be different from the known cephalosporin C acylase producer SE83 in their abilities to reduce nitrate and to utilize several organic acids and sugars.