Abstract
N-ethyl-maleimide alkylation converts ferric P450cam to a (succinimido-cys)4 protein with native optical and EPR spectra but insensitive to substrate induced shift of iron to high spin with Soret absorption to higher energy and inactive in putidaredoxin ferric-ferrous reduction. On photo or chemical reduction the ferrous protein oxygenates and, with reduced putidaredoxin, converts substrate to product. Mild oxidation of P450cam yields a disulfide dimer whose properties on alkylation of 3 sulfhydryls equal the succinimido4 monomer; additional alkylation converts either monomer or dimer to a P420.
Original language | English (US) |
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Pages (from-to) | 771-778 |
Number of pages | 8 |
Journal | Biochemical and Biophysical Research Communications |
Volume | 83 |
Issue number | 3 |
DOIs | |
State | Published - Aug 14 1978 |
Externally published | Yes |
Bibliographical note
Funding Information:Supported in part by HEW PHS Grants GM 21161 and AM 00562. We are indebted to Dr. B. S. Shastry for checking the cysteinyl and succinimido-cysteine content of the NEM treated cyt m.