Centre de recherche en bactériologie, Institut Armand-Frappier, Université du Québec, Laval, Québec H7N 4Z3, Canada.
Appl Environ Microbiol. 1983 Jul;46(1):17-21. doi: 10.1128/aem.46.1.17-21.1983.
Cellobiase (beta-glucosidase) production was compared for two streptomycetes: Streptomyces flavogriseus, a known producer of cellulase complex, and Streptomyces sp. strain CB-12, a strain isolated for its rapid growth on cellobiose. The optimal conditions for enzyme activity were established in relation to pH, temperature, enzyme stability, and substrate affinity. The production of beta-glucosidase by the two strains depended on the carbon substrate in the medium. Cellobiose was found to repress the biosynthesis of the enzyme in S. flavogriseus and to stimulate its production in strain CB-12. The biosynthesis of the enzyme correlated well with the accumulation of glucose in the culture filtrates. The combined action of the beta-glucosidases produced by the two Streptomyces strains might allow a better utilization of the reaction products which arise during the biodegradation of cellulose.
比较了两种链霉菌产纤维二糖酶（β-葡萄糖苷酶）的情况：产纤维素酶复合物的已知菌——黄色链霉菌和一株以纤维二糖为唯一碳源快速生长的链霉菌 sp. 菌株 CB-12。考察了酶活与 pH 值、温度、酶稳定性和底物亲和力之间的最优关系。两种菌产β-葡萄糖苷酶的情况依赖于培养基中的碳源。结果表明，纤维二糖对 S. flavogriseus 中该酶的生物合成起阻遏作用，而对 CB-12 菌株的产酶则起诱导作用。酶的生物合成与培养液中葡萄糖的积累密切相关。两种链霉菌产生的β-葡萄糖苷酶的协同作用可能有利于更好地利用纤维素生物降解过程中产生的反应产物。
