Ganghofner D, Kellermann J, Staudenbauer W L, Bronnenmeier K
Institute for Microbiology, Technical University of Munich, Germany.
Biosci Biotechnol Biochem. 1998 Feb;62(2):302-8. doi: 10.1271/bbb.62.302.
Thermoanaerobic bacteria are of considerable interest as producers of thermostable amylolytic enzymes. The soluble amylolytic enzyme system of Thermoanaerobacterium thermosaccharolyticum DSM 571 was fractionated into a pullulanase, a glucoamylase, and an alpha-glucosidase. The enzymes were purified to homogeneity and their physical and catalytic properties were studied. The pullulanase, which cleaved both alpha-1,4- and alpha-1,6-glucosidic bonds, was an amylopullulanase closely related to similar enzymes from other thermoanaerobic bacteria. Partial amino acid sequences of the glucoamylase were identical with the corresponding sequences deduced from the cga gene encoding the glucoamylase from Clostridium sp. strain G0005. The alpha-glucosidase was identified as an isomaltase belonging to a group of structurally related exo-alpha-1,4-glucosidases and oligo-1,6-glucosidases from bacilli. Comparison of enzyme activities indicated that the glucoamylase had the major amylolytic activity of T. thermosaccharolyticum, with amylopullulanase and alpha-glucosidase assisting in the cleavage of alpha-1,6-glucosidic bonds.
作为热稳定淀粉酶的生产者，嗜热厌氧菌备受关注。嗜热解糖嗜热厌氧菌DSM 571的可溶性淀粉酶系统被分离为支链淀粉酶、糖化酶和α-葡萄糖苷酶。这些酶被纯化至同质，并对其物理和催化特性进行了研究。该支链淀粉酶可切割α-1,4-和α-1,6-糖苷键，是一种与其他嗜热厌氧菌的类似酶密切相关的支链淀粉酶。糖化酶的部分氨基酸序列与从编码梭菌属菌株G0005糖化酶的cga基因推导的相应序列相同。α-葡萄糖苷酶被鉴定为一种异麦芽糖酶，属于芽孢杆菌属中一组结构相关的外切α-1,4-葡萄糖苷酶和寡聚-1,6-葡萄糖苷酶。酶活性比较表明，糖化酶具有嗜热解糖嗜热厌氧菌的主要淀粉酶活性，支链淀粉酶和α-葡萄糖苷酶协助切割α-1,6-糖苷键。
