Reductases for carbonyl compounds in human liver

Toshihiro Nakayama, Akira Hara, Koji Yashiro, Hideo Sawada

研究成果: Article査読

67 被引用数 (Scopus)

抄録

Two aldehyde reductases with mol. wt 78,000 and 32,000 and one carbonyl reductase with mol. wt 31,000 were purified to homogeneity from human liver cytosol. The high molecular weight aldehyde reductase exhibited properties similar to alcohol dehydrogenase; it had a single subunit of mol. wt 41,000 and a pI value of 10 to 10.5, and showed preference for NADH over NADPH as cofactor and sensitivity to SH-reagents, pyrazole, o-phenanthroline and isobutyramide. The enzyme reduced aliphatic and aromatic aldehydes, alicyclic ketones and α-diketones and an optimal pH of 6.0, and oxidized various alcohols with NAD as a cofactor at an optimal pH of 8.8. The identity of the enzyme with alcohol dehydrogenase was established by starch gel electrophoresis and co-purification of the two enzymes. The other enzymes were NADPH-dependent and monomeric reductases; the aldehyde reductase reduced aldehydes, hexonates and α-diketones and was sensitive to barbiturates, diphenylhydantoin and valproate, while the carbonyl reductase showed a broad substrate specificity for aldehydes, ketones and quinones and was inhibited by SH-reagent, quercitrin and benzoic acid. The latter enzyme appeared in three multiforms with different charges which occurred in differing ratios in liver specimens. Comparison of kinetic constants for aldehydes among the enzymes indicated that alcohol dehydrogenase is the best reductase with the highest affinity and Kcat values. The enzyme also catalyzed oxidation and reduction of aromatic aldehydes in the presence of NAD at physiological pH of 7.2. Tissue distribution of the three enzymes and variation of their specific activities in human livers were examined.

本文言語English
ページ(範囲)107-117
ページ数11
ジャーナルBiochemical Pharmacology
34
1
DOI
出版ステータスPublished - 01-01-1985
外部発表はい

All Science Journal Classification (ASJC) codes

  • Biochemistry
  • Pharmacology

フィンガープリント 「Reductases for carbonyl compounds in human liver」の研究トピックを掘り下げます。これらがまとまってユニークなフィンガープリントを構成します。

引用スタイル