title: [Transformation of delta4-3-ketosteroids by free and immobilized cells of Rhodococcus erythropolis actinobacterium].
abstract: 9alpha-Hydroxy derivatives were prepared from 11 steroids ofandrostane and pregnane series using Rhodococcus erythropolis VKPM Ac-1740 culture with 0.5-20 g/l substrate concentration in the reaction mixture. 9alpha-Monohydroxylation proceeded regardless of the substituent structure at C17. However, the structure of the steroid molecule influenced the time of complete conversion of the substrate and the yield of the transformation product. 9alpha-Hydroxy-androstenedione was obtained in 35 h in a yield of 85% when the maximum concentration of androstenedione (AD) was 10 g/l. 9alpha-Hydroxy-AD was also formed by the actinobacterium cells entrapped in poly(vinyl alcohol) cryogel beads. Nine successive transformation cycles were carried out using immobilized cells at 4.0 g/l concentration of AD in the medium. The yield of 9alpha-hydroxy-AD formed during six cycles (from two to eight with the duration of each cycle for 22-24 h) was 98%.
authors.forename: N V
authors.initials: NV
authors.lastname: Karpova
authors.forename: V A
authors.initials: VA
authors.lastname: Andriushina
authors.forename: V V
authors.initials: VV
authors.lastname: Iaderets
authors.forename: A V
authors.initials: AV
authors.lastname: Druzhinina
authors.forename: T S
authors.initials: TS
authors.lastname: Stytsenko
authors.forename: B L
authors.initials: BL
authors.lastname: Shaskol'skiĭ
authors.forename: V I
authors.initials: VI
authors.lastname: Lozinskiĭ
authors.forename: L'iu Duk
authors.initials: LD
authors.lastname: Khi
authors.forename: N E
authors.initials: NE
authors.lastname: Voĭshvillo
mesh_terms: D000735:Androstenedione / Q000096:biosynthesis* / Q000737:chemistry / Q000302:isolation & purification; D055162:Biocatalysis; D019149:Bioreactors; D001711:Biotransformation; D018914:Cells, Immobilized / Q000166:cytology / Q000378:metabolism*; D002855:Chromatography, Thin Layer; D003470:Culture Media; D006900:Hydroxylation; D006914:Hydroxysteroids / Q000737:chemistry / Q000302:isolation & purification / Q000378:metabolism*; D007218:Industrial Microbiology / Q000379:methods*; D007700:Kinetics; D009682:Magnetic Resonance Spectroscopy; D013058:Mass Spectrometry; D011142:Polyvinyl Alcohol / Q000737:chemistry; D012240:Rhodococcus / Q000737:chemistry / Q000378:metabolism*; D013237:Stereoisomerism
chemical_list: D003470:Culture Media; D006914:Hydroxysteroids; D000735:Androstenedione; D011142:Polyvinyl Alcohol