title: Stability of immobilized maltotetraose-forming amylase from Pseudomonas stutzeri.
abstract: The stability of immobilized maltotetraose (G(4))-forming amylase (1,4-alpha-D-glucan maltoteraohydrolase, EC 3.2.1.60) from Pseudomonas stutzeri was investigated in both batch and continuous processes. The inactivation process of the immobilized enzyme seemed to obey first-order kinetics, and the immobilized enzyme became more stable when coexisting with 20-30 wt % substrate and calcium ions. From intensive studies on the operational stability in the continuous process, the apparent half-life of G(4) productivity in a constant-flow system was mainly affected by the reaction temperature, substrate concentration, and initial immobilized enzyme activity. A new factor, immobilized enzyme stability factor f(s), was proposed to evaluate the half-life of the immobilized enzyme system.
authors.affiliation: Engineering and Development Division, Chiyoda Corporation, 3-13 Moriya-cho, Kanagawa-ku, Yokohama 213, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Kimura
authors.forename: M
authors.initials: M
authors.lastname: Ogata
authors.forename: M
authors.initials: M
authors.lastname: Yoshida
authors.forename: T
authors.initials: T
authors.lastname: Nakakuki