Microbial side-chain degradation of ergosterol and its 3-substituted derivatives: a new route for obtaining of deltanoids.
The strain of Mycobacterium sp. VKM Ac-1815D was found to convert ergosterol and its 3-acetate mainly to androst-4-ene-3,17-dione (AD) thus demonstrating ability to reduce 7(8)-double bond and hydrolyze sterol ester in addition to oxidation of 3beta-hydroxy group, Delta(5)-Delta(4) isomerization and side-chain degradation. Ergosterol bioconversion in the presence of isoflavones and ions of some bivalent metals - known inhibitors of 3beta-hydroxysteroid dehydrogenase, did not alter products composition. Protection of ergosterol 3beta-hydroxyl with methoxymethyl group allowed the formation of bioconversion products retaining the Delta(5,7)-configuration. The major product was identified by mass-spectrometry and proton NMR as 3-methoxymethoxy-androsta-5,7-diene-17-one (MA). The MA producing activity was found to be inducible with sterols, cholestenone or lithocholic acid, but not with dehydroepiandrosterone, AD, androsta-1,4-ene-3,17-dione or organic acids. Under the optimized conditions, the yield of MA reached 5g/l from 10g/l O-methoxymethyl-ergosterol (approx. 60% molar conversion) for 120h. The results might be applied at the production of novel vitamin D derivatives.
Dovbnya
Dmitry V
DV
G.K. Skryabin Institute of Biochemistry & Physiology of Microorganisms Russian Academy of Sciences, Pushchino, Moscow Region, 142290, Russia. anagoge@rambler.ru
Egorova
Olga V
OV
Donova
Marina V
MV
D000734:Androstenediols / Q000737:chemistry / Q000378:metabolism; D002855:Chromatography, Thin Layer; D004875:Ergosterol / Q000737:chemistry / Q000378:metabolism*; D009682:Magnetic Resonance Spectroscopy; D013058:Mass Spectrometry; D015394:Molecular Structure; D009161:Mycobacterium / Q000378:metabolism*; D012855:Sitosterols / Q000737:chemistry / Q000378:metabolism
D000734:Androstenediols; D012855:Sitosterols; C025473:gamma-sitosterol; D004875:Ergosterol