Biologia, Bratislava, 57/Suppl. 11: 83-85, 2002.

ISSN 0006-3088 (Biologia).

 

Review

Macromolecule recognition of Bacillus stearothermophilus neopullulanase.

 

Hiroshi Kamasaka, Kazuhisa Sugimoto, Hiroki Takata, Takahisa Nishimura & Takashi Kuriki*

 

Biochemical Research Laboratory, Ezaki Glico Co., Ltd., 4-6-5 Utajima, Nishiyodogawa-ku, Osaka 555-8502, Japan; tel.: ++ 81 6 6477 8425, fax: ++ 81 6 6477 8362, e-mail: kuriki-takashi@glico.co.jp

* corresponding author

Received: October 4, 2001 / Accepted: February 12, 2002

 

Abstract

Neopullulanase was a key enzyme in opening the door to clarification of the concept of the a-amylase family. The enzyme catalyzes both hydrolysis and transglycosylation of a-1,4- and a-1,6-glucosidic linkages at one active center. Different activities of neopullulanase toward amylose and amylopectin was noted previously. We recently found a unique way, using macromolecules, for recognition of the enzyme. A mixture of amylose and amylopectin from various sources was used as the substrate. Neopullulanase completely hydrolyzed amylose, but scarcely affected amylopectin. Although the molecular mass of amylopectin (approximately 108 Da) decreased slightly, the degradation of amylopectin completely halted at the molecular weight of approximately 107 Da. This difference in action on two macromolecules was also found in cyclomaltodextrinase and maltogenic amylase from Bacillus licheniformis.

 

Key words: neopullulanase, cyclomaltodextrinase, maltogenic amylase, amylose, amylopectin.