TY - BOOK AU - Mukai,K. AU - Yamada,K. AU - Doit,Y. TI - Kinetics and mechanism of heterogeneous hydrolysis of poly[(R)-3-hydroxybutyrate]fielm by PHA depolymerases KW - ENZYMATIC DEGRADATION KW - PHA DEPOLYMERASES KW - POLY[(R)-3-HYDROXYBUTYRATE] KW - HETEROGENEOUS HYDROLYSIS KW - KINETIC MODEL N2 - The kinetics and mechanism of enzymatic degradation on the surface of poly[(R)-3-hydroxybutyrate](PC(R)-3HB]) jilm have been studied using three types of extracellular poly(hydroxyalkanoate)(PHA)depolymerases from Alcaligenes faecalis, Pseudomonas pickettii and Comamonas testosteroni. The monomer and dimer of 3-hydroxybutyric acid were produced during the course of the enzymatic degradation of PC(R)-3HB]film, and the rate of production was determined by monitoring the increase in absorbance at 210 nm on a spectrophotometer. The rate of enzymatic degradation increased to a maximum value with the concentration of PHA depolymerase, followed by a gradual decrease. The kinetic data were accountedfor in terms of a heterogeneous enzymatic reaction, involving enzymatic degradation on the surface of PC(R)-3HB]jilm via two steps of adsorption and hydrolysis by a PHA depolymerase with binding and catalytic domains. The kinetic results suggest that the properties oj-the catalytic domains are very similar among the three PHA depolymerases, but that those of the binding domains are strongly dependent on the type of depolymerase UR - https://drive.google.com/file/d/13VXs7PmxOF3YZjJ9xswQ2fgDIC6LDAnA/view?usp=drivesdk ER -