Irrgang S, Schlosser D, Fritsche W
Friedrich-Schiller-Universität Jena, Biologisch-Pharmazeutische Fakultät, Institut für Mikrobiologie, Lehrstuhl Technische Mikrobiologie, Germany.
J Steroid Biochem Mol Biol. 1997 Mar;60(5-6):339-46. doi: 10.1016/s0960-0760(96)00185-9.
The 15alpha-hydroxylation of 13-ethyl-gon-4-ene-3,17-dione (GD) with different subcellular fractions of Penicillium raistrickii i 477 was investigated. Cytochrome P-450 was shown to be involved in this reaction. The steroid transformation was inhibited by carbon monoxide, metyrapone, p-CMB, iodoacetamide, N-methylmaleimide and several metal ions. The 15alpha-hydroxylase was observed to be dependent on nicotinamide-adenine dinucleotide phosphate (NADPH) replaceable by NaIO4, and the activity was enhanced by a NADPH-regenerating system, indicating the involvement of the NADPH-cytochrome c (P-450) reductase. This was further confirmed by the inhibition of the hydroxylase activity in the presence of cytochrome c. No effect was observed in the presence of azide and antimycin A. Solubilized microsomes gave an absorption maximum at 453 nm in carbon monoxide difference spectrum, and showed a Type-I GD-binding spectrum typically for cytochrome P-450 interaction with substrate. First results about the inducibility of the enzymes involved in the 15alpha-hydroxylation of GD are shown.
研究了用赖氏青霉i 477的不同亚细胞组分对13-乙基-4-烯-3,17-二酮（GD）进行15α-羟基化反应。结果表明细胞色素P-450参与了该反应。一氧化碳、美替拉酮、对氯汞苯甲酸、碘乙酰胺、N-甲基马来酰亚胺和几种金属离子可抑制甾体转化。观察到15α-羟化酶依赖于可被高碘酸钠替代的烟酰胺腺嘌呤二核苷酸磷酸（NADPH），并且NADPH再生系统可增强其活性，这表明NADPH-细胞色素c（P-450）还原酶参与其中。在细胞色素c存在的情况下羟化酶活性受到抑制进一步证实了这一点。在叠氮化物和抗霉素A存在的情况下未观察到影响。溶解的微粒体在一氧化碳差光谱中在453nm处有最大吸收，并显示出典型的细胞色素P-450与底物相互作用的I型GD结合光谱。展示了关于GD 15α-羟基化反应中所涉及酶的诱导性的初步结果。
