title: Production of malodorous steroids from androsta-5,16-dienes and androsta-4,16-dienes by Corynebacteria and other human axillary bacteria.
abstract: The biotransformations of a number of steroids, chiefly 5,6,16,17-tetradehydro-androstanes, are reported. The strains investigated were Corynebacteria sp. G38, G40, G41, B, Brevis sp. CW5 and Micrococcus sp. M-DH2. Corynebacterium sp. G41 proved remarkably efficient in effecting oxidative isomerisation of 5-ene-3-sterols into the corresponding 4-en-3-ones. The main biochemical reactions involved were oxidation at C-3; no reduction processes were observed. Conversions of 3beta-sterols into the C-3 oxo-steroids were high, but were correspondingly low for the 3alpha-sterol epimers. Androsta-4,16-dien-3-one and 5beta-androsta-16-en-3-one are crucial to the formation of malodour. The rate of formation of these compounds was measured over 72 h incubation periods using three substrates: androsta-5,16-dien-3beta-ol, androsta-4,16-dien-3beta-ol and androsta-5,16-dien-3-one. Induction studies of the transformation of the androsta-5,16-dien-3beta-ol into the very odorous compound androsta-4,16-dien-3-one showed that cells incubated with a mixture of antibiotics displayed the same extent of biotransformation as normal cells if the concentration of antibiotic was low (1, 3, 5 and 7 microg/ml), although at concentrations higher than 10 microg/ml, biotransformation yields were reduced. Pre-incubation with a 3beta-fluoro-steroid inhibited the formation of the odorous androsta-4,16-dien-3-one.
authors.affiliation: Christopher Ingold Laboratories, Department of Chemistry, University College London, 20 Gordon Street, WC1H 0AJ London, UK.
authors.forename: Richard A
authors.initials: RA
authors.lastname: Decréau
authors.forename: Charles M
authors.initials: CM
authors.lastname: Marson
authors.forename: Kelvin E
authors.initials: KE
authors.lastname: Smith
authors.forename: John M
authors.initials: JM
authors.lastname: Behan
mesh_terms: D000192:Actinomycetales / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*; D000693:Anaerobiosis; D000730:Androstadienes / Q000737:chemistry / Q000378:metabolism*; D000737:Androstenols / Q000737:chemistry / Q000378:metabolism; D001365:Axilla / Q000382:microbiology; D001711:Biotransformation; D002851:Chromatography, High Pressure Liquid; D002855:Chromatography, Thin Layer; D003470:Culture Media; D006801:Humans; D009812:Odorants; D010084:Oxidation-Reduction; D013045:Species Specificity; D013237:Stereoisomerism; D013256:Steroids / Q000096:biosynthesis* / Q000737:chemistry; D013997:Time Factors
chemical_list: D000730:Androstadienes; D000737:Androstenols; D003470:Culture Media; D013256:Steroids