Enzymatic ω-Oxidation

Abstract

Molecularoxygen and reduced diphosphopyridine nucleotide are required for the hydroxylation of octane, yielding n-octanol, in a soluble enzyme system from Pseudomonas oleovorans previously shown to hydroxylate fatty acids at the w carbon atom.Hexane and decane are also oxidized, but at lower rates.Procedures are described for the separation and partial purification of the three bacterial protein components required for fatty acid and hydrocarbon hydroxylation: rubredoxin (a red, nonheme iron protein containing no labile sulfide), a reduced diphosphopyridine nucleotide-rubredoxin reductase, and the w-hydroxylase.Electron transfer occurs from reduced diphosphopyridine nucleotide to rubredoxin, catalyzed by the reductase, and from reduced rubredoxin to cytochrome c.Evidence is presented that rubredoxin and the reductase function in a similar manner as electron carriers during substrate hydroxylation in the presence of the w-hydroxylase.Since the discovery by Verkade et al. (1) of the biological oxidation of fatty acids at the w carbon atom, many examples