Immobilization of Yeast Microbodies by Inclusion with Photo‐crosslinkable Resins

Abstract

Yeast microbodies containing FAD‐dependent alcohol oxidase, catalase and D‐amino acid oxidase were isolated from methanol‐grown cells of Kloeckera sp. 2201 and immobilized intact in matrices formed by a short‐time illumination of photo‐crosslinkable resin oligomers. The relative activities of catalase, alcohol oxidase and D‐amino acid oxidase of the gel‐entrapped microbodies were 36, 76 and 31% respectively as compared with those of free microbodies. Immobilization enhanced the stability of catalase to a certain degree, but not that of alcohol oxidase. The pH/activity profiles of catalase and alcohol oxidase of the entrapped organelles showed more narrow pH optima than those of the free counterparts. D‐Amino acid oxidase in immobilized microbodies showed a somewhat higher K_m value for D‐alanine than that in free ones. Immobilized microbodies oxidized two moles of methanol to form two moles of formaldehyde with consumption of one mole of molecular oxygen. Addition of 3‐amino‐1,2,4‐triazole, an inhibitor of catalase, reduced the formation of formaldehyde to half the amount without change in the amount of oxygen consumed, indicating the synergic action of alcohol oxidase and catalase in methanol oxidation in the microbodies of living yeast cells.