S. Voigt, M. Luckner
1977
Citations
0
Influential Citations
12
Citations
Journal
Phytochemistry
Abstract
Abstract Dehydrocyclopeptine epoxidase (DE) activity was determined in cell free preparations of Penicillium cyclopium . The enzyme transforms dehydrocyclopeptine into cyclopenin by a mixed function oxygenation. It needs molecular oxygen and uses NAD(P)H, ascorbate or d , l -6-methyl-5,6,7,8-tetrahydropteridine as cosubstrates. DE is inhibited by CN − , SCN − , 1,10-phenanthroline, EDTA, 2,2′-bipyridine, sodium diethyldithiocarbamate, dicoumarol, p -chloromercuribenzoate and ions of different heavy metals, but not by CO and the lead salt of diethyldithiocarbamate. These properties indicate a specific importance of Fe 2+ -ions, SH-groups and flavins. DE activity is increased by Fe 2+ and FAD. The enzyme may be therefore a Fe 2+ activated FAD containing flavoprotein. DE was enriched 268-fold by (NH 4 ) 2 SO 4 precipitation and chromatography on Sephadex G-200. Its MW estimated by Sephadex chromatography, exceeds 480 000.