Properties of purified kidney microsomal NADPH-cytochrome c reductase

Lucy Liou Fan, Bettie Sue Siler Masters

Research output: Contribution to journalArticle

28 Scopus citations

Abstract

NADPH-cytochrome c reductase, solubilized by lipase digestion of microsomes prepared from perfused porcine kidney cortex, was purified about 3600-fold to give a turnover number of 1230 nmoles cytochrome c reduced per min per nmole flavin. The kinetic determination of Km and V with respect to NADPH, cytochrome c, and NADH, resulted in values similar to those obtained with purified liver reductase. The kidney microsomal enzyme also exhibited a ping-pong kinetic mechanism for NADPH-mediated cytochrome c reduction. Spectrofluorometric measurements demonstrated the presence of equimolar amounts of FAD and FMN per mole of reductase. The molecular weight was estimated by Sephadex G-200 gel filtration and sodium dodecyl sulfate polyacrylamide gel electrophoresis to be 68,000 and 71,000 g per mole, respectively. Immunochemical techniques, including Ouchterlony double-diffusion studies and inhibition of catalytic activity by antibody to the liver microsomal NADPH-cytochrome c reductase, established the similarity of the purified liver and kidney reductases.

Original languageEnglish (US)
Pages (from-to)665-671
Number of pages7
JournalArchives of Biochemistry and Biophysics
Volume165
Issue number2
DOIs
StatePublished - Dec 1974

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ASJC Scopus subject areas

  • Biophysics
  • Biochemistry
  • Molecular Biology

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