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Structures of Mitochondrial P450 System Proteins

  • Israel Hanukoglu
Part of the NATO ASI Series book series (NSSA, volume 303)

Abstract

Mitochondrial P450 type enzymes are generally involved in the metabolism of cho lesterol derived steroidal compounds. The reactions catalyzed by these enzymes include cholesterol conversion to pregnenolone, 11-beta and 18 hydroxylation reactions in adrenal steroid biosynthesis, C-27 hydroxylation of cholic acid in bile acid metabolism, and 1al pha and 24 hydroxylations of vitamin D. These P450 mediated reactions require molecular oxygen and two electrons donated by NADPH. The electrons of NADPH are transferred to P450 by an electron transfer system that includes a specific flavoprotein, adrenodoxin reductase, and an iron-sulfur protein, adrenodoxin. These proteins are not specific for indi vidual P450s and serve as electron donors for different P450 in different tissues. This review presents an overview of the major sequence and structural characteristics of the mitochondrial P450 system proteins.

Keywords

Adrenal Cortex Cholic Acid Mature Peptide Spirulina Platensis Bile Acid Metabolism 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Springer Science+Business Media New York 1999

Authors and Affiliations

  • Israel Hanukoglu
    • 1
  1. 1.E. Katzir Biotechnology Program, The Research InstituteThe College of Judea and SamariaArielIsrael

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