摘要 |
PCT No. PCT/EP95/02883 Sec. 371 Date Jan. 8, 1997 Sec. 102(e) Date Jan. 8, 1997 PCT Filed Jul. 19, 1995 PCT Pub. No. WO96/03518 PCT Pub. Date Feb. 8, 1996The invention concerns a process for preparing mercapto compounds comprising the step of demethylating an S-methyl-mercapto compound of Formula I to the corresponding mercapto compound of Formula II, using a microorganism which is capable of demethylating S-methyl-3-mercapto-propionate (MMPA) to 3-mercaptopropionate (MPA) or using an enzyme preparation derivable from such microorganism. <IMAGE> Preferably the group R denotes CH2-CH2-COOH (I is MMPA), CH2-CH(NH2)-COOH (I is S-methyl-cystein), CH2-CH2-CH(NH2)-COOH (I is methionine) and CH2-COOH (I is methylmercapto-acetate) or a salt or ester of any of these. Preferably the microorganisms are methanogenic archaea of the genus Methanosarcina or obtained by inocculating a suitable medium containing MMPA with salt marsh or marine sediment followed by one or more transfers into fresh medium containing MMPA and suppression of the growth of Bacteria, but not of Archaea in the culture e.g. with an antibiotic. |