Production, purification and characterization of glucose oxidase from Penicillium variabile P16

摘要

Glucose oxidase was produced by Penicillium variabile P16 grown in a benchtop bioreactor and purified 30-fold to homogeneity by ion-exchange and gel-filtration chromatography. The M_r of the native enzyme was 126000 and that of the subunit 62000, which indicated that the native enzyme is a dimer. The enzyme was optimally active at pH 6.0 and 55℃ and highly specific for β-D-glucose (K_m 6.0 mM). Two isoenzymes, with pI values of 4.8-4.9, were detected on analytical isoelectric-focusing gels. The glucose oxidase was severely inhibited by Cu~(2+) and Ag~+ ions and, to a lower extent, by NaF.