Purification and some properties of hamster liver aldehyde oxidase

Aldehyde oxidase was purified from hamster liver cytosol by ammonium sulfate fractionation, chromatography on DEAE-cellulose and Phenyl-Toyopearl, and HPLC-gel filtration on TSK-gel G3000SW(XL) column. The purified enzyme was homogeneous by the criterion of sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). Its molecular weight was determined to be 144800 by SDS-PAGE and 288000 by HPLC gel filtration. The isoelectric point was pH 5.1. The apparent Km and Vmax for benzaldehyde and 2-hydroxypyrimidine were 19.0 and 4.4 microM, and 165 and 211 nmol/min/mg protein, respectively. The benzaldehyde oxidase activity was markedly inhibited by menadione and chlorpromazine. The substrate specificity was different from those of the enzymes from other animals.