Mossbauer studies of alkane omega-hydroxylase: evidence for a diiron cluster in an integral-membrane enzyme.

ABSTRACT: The gene encoding the alkane omega-hydroxylase (AlkB; EC 1.14.15.3) from Pseudomonas oleovorans was expressed in Escherichia coli. The integral-membrane protein was purified as nearly homogeneous protein vesicles by differential ultracentrifugation and HPLC cation exchange chromatography without the detergent solubilization normally required for membrane proteins. Purified AlkB had specific activity of up to 5 units/mg for octane-dependent NADPH consumption. Mössbauer studies of AlkB showed that it contains an exchange-coupled dinuclear iron cluster of the type found in soluble diiron proteins such as hemerythrin, ribonucleotide reductase, methane monooxygenase, stearoyl-acyl carrier protein (ACP) delta9 desaturase, rubrerythrin, and purple acid phosphatase. In the as-isolated enzyme, the

SUBMITTER: Shanklin J 

PROVIDER: S-EPMC20308 | biostudies-literature | 1997 Apr

REPOSITORIES: biostudies-literature