抄録
1. The protein fraction which catalyzes pyridoxine oxidation in the presence of aldehyde oxidase preparation was purified from rabbit liver extracts.
2. The pyridoxine oxidizing enzyme system showed the highest activity at pH 5.7 to 5.9.
3. The ability of Fraction PO to oxidise pyridoxine was dependent on the presence of aldehyde oxidase preparation from rabbit liver.
4. The pyridoxine oxidizing activity in the crude extracts was enhanced by the addition of ferrous ion, manganese ion and some aliphatic alcohols. The stimulatory action of these metal ions was not observed with a purified preparation.
5. 4-Deoxypyridoxine competitively inhibited the oxidation of pyridoxine.
6. No electron acceptor in this reaction could be identified in the liver system. However, a preliminary experiment with the yeast enzyme revealed a requirement for TPNH in the conversion of pyridoxal to pyridoxine.
7. The distribution of the pyridoxine oxidizing activity was studied in several mammalian tissues.
