title: Occurrence and subcellular location of NADH- and NADPH-linked aquacobalamin reductases in human liver.
abstract: 1. Both activities of NADH- and NADPH-linked aquacobalamin reductases were found in some human tissues, liver, kidney pancreas, heart, spleen, lung, cerebrum, cerebellum, adrenal glands, stomach, duodenum, jejunum, ileum, colon and bone marrow. 2. Human liver contained both enzymes with higher specific activities than any other tissues. 3. The liver NADH-linked enzyme was distributed in both mitochondrial (approx. 60%) and microsomal (40%) fractions; similar to the distribution of the NADPH-linked enzyme, but of which 40% activity was found in the mitochondria and the remaining activity was recovered in the microsomes. 4. The results suggest that the synthetic systems of the cobalamin coenzymes occur in both mitochondria and microsomes of human liver.
authors.affiliation: Laboratory of Nutrition and Food Science, Hagoromo-gakuen College, Osaka, Japan.
authors.forename: F
authors.initials: F
authors.lastname: Watanabe
authors.forename: Y
authors.initials: Y
authors.lastname: Nakano
authors.forename: N
authors.initials: N
authors.lastname: Tachikake
authors.forename: S
authors.initials: S
authors.lastname: Kitaoka
authors.forename: Y
authors.initials: Y
authors.lastname: Tamura
authors.forename: H
authors.initials: H
authors.lastname: Yamanaka
authors.forename: S
authors.initials: S
authors.lastname: Haga
authors.forename: S
authors.initials: S
authors.lastname: Imai
authors.forename: H
authors.initials: H
authors.lastname: Saido
mesh_terms: D002458:Cell Fractionation; D006801:Humans; D008099:Liver / Q000201:enzymology*; D009247:NADH, NADPH Oxidoreductases / Q000032:analysis*; D009928:Organ Specificity
chemical_list: C068157:aquacobalamin reductase; C053436:aquacobalamin reductase (NADPH); D009247:NADH, NADPH Oxidoreductases