Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0030567 (Parkinson's disease)
 63,064 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Dopamine-HCl and L-DOPA-alpha-glycosides were prepared by reaction with cyclomaltohexaose, catalyzed by Bacillus macerans cyclomaltodextrin glucanyltransferase. The reaction gave maltodextrins attached to dopamine and L-DOPA; the maltodextrins were trimmed by reactions with glucoamylase and beta-amylase to produce alpha-glucosyl- and alpha-maltosyl-glycosides, respectively. The glucoamylase- or beta-amylase-treated dopamine- and L-DOPA-alpha-glycosides were fractionated and purified by BioGel P-2 gel-filtration column chromatography and preparative descending paper chromatography. Analysis by MALDI-TOF mass spectrometry and one- and two-dimensional NMR showed that the purified glycosides of dopamine and L-DOPA were glycosylated at the hydroxyl groups of positions 3 and 4 of the catechol ring. The major product was found to be 4-O-alpha-glycopyranosyl L-DOPA, and it was shown to be more resistant to oxidative tolerance experiments, involving hydrogen peroxide and ferrous ion, than L-DOPA. L-DOPA-alpha-glycosides are possibly more effective substitutes for L-DOPA in treating Parkinson's disease in that they are more resistant to oxidation and methylation, which renders L-DOPA ineffective and deleterious.
 ...
PMID:Synthesis of dopamine and L-DOPA-alpha-glycosides by reaction with cyclomaltohexaose catalyzed by cyclomaltodextrin glucanyltransferase. 1979 83

L-DOPA alpha-glycosides were synthesized by reaction of L-DOPA with sucrose, catalyzed by four different glucansucrases from Leuconostoc mesenteroides B-512FMC, B-742CB, B-1299A, and B-1355C. The glucansucrases catalyzed the transfer of d-glucose from sucrose to the phenolic hydroxyl position-3 and -4 of L-DOPA. The glycosides were fractionated and purified by Bio-Gel P-2 column chromatography, and the structures were determined by (1)H NMR spectroscopy. The major glycoside was 4-O-alpha-d-glucopyranosyl L-DOPA, and the minor glycoside was 3-O-alpha-D-glucopyranosyl L-DOPA. The two glycosides were formed by all four of the glucansucrases. The ratio of the 4-O-alpha-glycoside to the 3-O-alpha-glycoside produced by the B-512FMC dextransucrase was higher than that for the other three glucansucrases. The glycosylation of L-DOPA significantly reduced the oxidation of the phenolic hydroxyl groups, which prevents their methylation, potentially increasing the use of L-DOPA in the treatment of Parkinson's disease. The use of one enzyme, glucansucrase, and sucrose as the D-glucosyl donor makes the synthesis considerably simpler and cheaper than the formerly published procedure using cyclomaltodextrin and cyclomaltodextrin glucanyltransferase, followed by glucoamylase, and beta-amylase hydrolysis.
 ...
PMID:Enzymatic synthesis of L-DOPA alpha-glycosides by reaction with sucrose catalyzed by four different glucansucrases from four strains of Leuconostoc mesenteroides. 2057 35