Chemistry: molecular biology and microbiology – Micro-organism – tissue cell culture or enzyme using process... – Preparing sulfur-containing organic compound
Patent
1997-01-08
1998-09-29
Lilling, Herbert J.
Chemistry: molecular biology and microbiology
Micro-organism, tissue cell culture or enzyme using process...
Preparing sulfur-containing organic compound
4352521, C12P 1100, C12N 120
Patent
active
058144960
DESCRIPTION:
BRIEF SUMMARY
This application is the national phase of international application PCT/EP95/02883, filed Jul. 19, 1995.
The invention concerns a process for demethylating S-methyl-mercapto compounds. More particularly the invention concerns a process for microbiologically demethylating S-methyl-mercapto compounds to the corresponding mercapto compounds, such as S-methyl-3-mercaptopropionate to 3-mercaptopropionate.
Various mercapto compounds are useful as flavour components. Thus, 3-mercaptopropionate (hereinafter referred to as MPA for convenience) may be converted into its alkyl esters which, like MPA, are useful as flavour components.
S-methyl-mercaptopropionate (hereinafter referred to as "MMPA" for convenience) is known to be an intermediate in the degradation of 3-dimethylsulphoniumpropionate (also known as dimethyl-.beta.-propiothetin, but hereinafter referred to as DMSP for convenience) in anoxic marine coastal (or intertidal) sediments. A product of this degradation pathway is MPA and it was reported by R. P. Kiene and B. F. Taylor in Appl. Environ. Microbiol. 54: 2208-2212 (1988), and Nature 332: 148-150 (1988), that DMSP may be converted into MMPA which in turn is converted to MPA. MMPA and MPA are also intermediates in the metabolism of DMSP by certain aerobic bacteria, whereas other aerobic bacteria are known to degrade DMSP via an initial cleavage to acrylate and dimethyl sulphide (B. F. Taylor and D. C. Gilchrist, Appl. Environ. Microbiol. 57: 3581-3584 (1991)). Although MMPA is reported to be converted to MPA in coastal sediment (R. P. Kiene, vide supra and P. T. Visscher et al, FEMS Microbiol. Ecol. 14: 179-190 (1994)) the microorganisms responsible for this degradation were unknown and neither was anything known about the efficiency with which this takes place. Furthermore, it was noticed that in such sediments MMPA is also converted into methylmercaptan presumably with concomittant formation of acrylate. Finally, MPA is further metabolized via yet unknown pathways.
It has now been found that certain mercapto compounds can be prepared using a process which comprises the step of demethylating an S-methyl-mercapto compound of general formula I to the corresponding mercapto compound of general formula II, using a microorganism which is capable of demethylating MMPA to MPA, or using an enzyme preparation derivable from such microorganism. ##STR2##
In these general formulae R denotes an alkyl radical derived from an alkane carboxylic acid or a derivative thereof. Examples of such radicals are: CH.sub.2 --CH.sub.2 --COOH (I is MMPA), CH.sub.2 --CH(NH.sub.2)--COOH (I is S-methyl-cystein), CH.sub.2 --CH.sub.2 --CH(NH.sub.2)--COOH (I is methionine) and CH.sub.2 --COOH (I is methylmercaptoacetate) and salts or esters of any of these. Such starting materials and various others for the demethylation according to the invention can be prepared from the corresponding dimethylsulphonium compounds by demethylation, whereas these dimethylsulphonium compounds in turn may be found in nature e.g. in various marine organisms and in brassica species and asparagus.
In the process the mercapto compound accumulates in the medium in which the microorganism is cultivated, respectively in the reaction medium in which the enzymatic reaction is carried out, and which contains the S-methylmercapto compound. The reaction product can be isolated therefrom. The process is especially useful for converting MMPA into MPA or derivatives of MMPA into derivatives of MPA.
Suitable microorganisms are methanogenic archaea, especially those occuring in marine and salt marsh sediments, particularly those of the family Methanosarcinaceae, more particularly of the genus Methanosarcina. Examples of such microorganisms are Methanosarcina strain MTP4 (DSM 6636, see also Finster et al, Arch. Microbiol. 157: 425-430 (1992)), Methanosarcina acetivorans (particularly DSM 2834) and Methanosarcina siciliae (particularly DSM 3028) or similar strains. Methanosarcina siciliae was previously known as Methanolobus siciliae; see S. Ni, Int. J. Syst. Bact. 44: 357-3
REFERENCES:
Derwent Biotech Abstract 95-01869 Visscher et al "Demethylation of dimethylsulfonopropionate to 3-mercaptoproprionate by an aerobic marine bacterium" Appl Environ. Microbio. (1994) 60, 12, 4617-4619.
Derwent Biotech Abstract 94-00586 Van der Maarel et al "Anaerobic degradatin of dimethylsulfoniopropionate to 3-S-methylsulfoniopropionate by a marine Desulfobacterium strain" Arch. Microbiol. (1993) 160, 411-12.
Derwent Biotech Abstract 93-14186 Visscher et al "Metabolism of dimethylsulfoniopropionate and nitrate-enhanced consumption of dimethyl sulfide in microbial mats" Abst. Gen Meet Am Soc. Microbiol (1993) 93 Meeting, 353.
Hansen Theo Adriaan
Jansen Michael
van der Maarel Marc Jos E. C.
Lilling Herbert J.
Quest International B.V.
LandOfFree
Process for demethylating S-methyl-mercapto compounds does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Process for demethylating S-methyl-mercapto compounds, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Process for demethylating S-methyl-mercapto compounds will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-685519