Stabilization of immobilized D-amino-acid oxidase was achieved as follows. Yeast Trigonopsis variabilis producing D-amino-acid oxidase was used to deaminate cephalosporin C to glutaryl-7-aminocephalosporanic acid. Permeabilized cells were co-immobilized with manganese dioxide by entrapment in (poly)acrylamide gel so that hydrogen peroxide, liberated in the reaction, could be partially deactivated and both the enzyme and the substrate could be stabilized. Activity of entrapped cells was determined by HPLC and enzyme flow microcalorimetry. The process was evaluated in terms of activity, immobilization yield, storage stability and oxo-product formation by immobilized preparations. The storage stability of immobilized biocatalysts with MnO2 was nearly doubled and production of 2-oxoadipyl-7-aminocephalosporanic acid was 2-3-fold higher than by entrapped cells without MnO2. Glutaryl-7-aminocephalosporanic acid can be easily obtained from the resulting oxo-product by a non-enzymic reaction via externally added hydrogen peroxide.

Institute of Chemistry Slovak Academy of Sciences Bratislava Slovakia

Zobrazit více v PubMed

Biotechnol Bioeng. 1995 Jun 20;46(6):510-3 PubMed

Biotechnol Bioeng. 1996 Jan 5;49(1):26-35 PubMed

Appl Biochem Biotechnol. 1981 Dec;6(4):293-307 PubMed

Enzyme Microb Technol. 1993 Jan;15(1):50-6 PubMed

D-amino-acid oxidase--an improved production of the enzyme by the yeast Trigonopsis variabilis in a laboratory fermentor