28449-15-2Relevant academic research and scientific papers
Effects of Alternative Redox Partners and Oxidizing Agents on CYP154C8 Catalytic Activity and Product Distribution
Dangi, Bikash,Park, Hyun,Oh, Tae-Jin
, p. 2273 - 2282 (2018)
CYP154C8 catalyzes the hydroxylation of diverse steroids, as has previously been demonstrated, by using an NADH-dependent system including putidaredoxin and putidaredoxin reductase as redox partner proteins carrying electrons from NADH. In other reactions, CYP154C8 reconstituted with spinach ferredoxin and NADPH-dependent ferredoxin reductase displayed catalytic activity different from that of the NADH-dependent system. The NADPH-dependent system showed multistep oxidation of progesterone and other substrates including androstenedione, testosterone, and nandrolone. (Diacetoxyiodo)benzene was employed to generate compound I (FeO3+), actively supporting the redox reactions catalyzed by CYP154C8. In addition to 16α-hydroxylation, progesterone and 11-oxoprogesterone also underwent hydroxylation at the 6β-position in reactions supported by (diacetoxyiodo)benzene. CYP154C8 was active in the presence of high concentrations (>10 mm) of H2O2, with optimum conversion surprisingly being achieved at ≈75 mm H2O2. More importantly, H2O2 tolerance by CYP154C8 was evident in the very low heme oxidation rate constant (K) even at high concentrations of H2O2. Our results demonstrate that alternative redox partners and oxidizing agents influence the catalytic efficiency and product distribution of a cytochrome P450 enzyme. More importantly, these choices affected the type and selectivity of reaction catalyzed by the P450 enzyme.
Biocatalyst mediated production of 6β,11α-dihydroxy derivatives of 4-ene-3-one steroids
Kolet, Swati P.,Niloferjahan, Siddiqui,Haldar, Saikat,Gonnade, Rajesh,Thulasiram, Hirekodathakallu V.
, p. 1152 - 1158 (2013/10/08)
Biotransformation of steroids with 4-ene-3-one functionality such as progesterone (I), testosterone (II), 17α-methyltestosterone (III), 4-androstene-3,17-dione (IV) and 19-nortestosterone (V) were studied by using a fungal system belonging to the genera of Mucor (M881). The fungal system efficiently and quantitatively converted these steroids in regio- and stereo-selective manner into corresponding 6β,11α-dihydroxy compounds. Time course experiments suggested that the transformation was initiated by hydroxylation at 6β- or 11α-(10β-hydroxy in case of V) to form monohydroxy derivatives which upon prolonged incubation were converted into corresponding 6β,11α-dihydroxy derivatives. The fermentation studies carried out using 5 L table-top fermentor with substrates (I and II) clearly indicates that 6β,11α-dihydroxy derivatives of steroids with 4-ene-3-one functionality can be produced in large scale by using M881.
