Methanolysis of ethyl esters of N-acetyl amino acids catalyzed by cyclosophoraoses isolated from Rhizobium meliloti.
Methanolysis of four ethyl esters, N-acetyl-L-phenylalanine ethyl ester, N-acetyl-l-tyrosine ethyl ester, N-acetyl-l-tryptophan ethyl ester, and ethyl phenylacetate was catalyzed by a mixture of microbial cyclooligosaccharides termed cyclosophoraoses isolated from Rhizobium meliloti. Cyclosophoraoses [cyclic-(1-->2)-beta-d-glucans, collectively 'Cys'] are a mixture of large-ring molecules consisting of various numbers of glucose residues (17-27) linked by beta-(1-->2)-glycosidic bonds. Cys as a catalytic carbohydrate enhanced the methanolysis about 233-fold for N-acetyl-L-tyrosine ethyl ester in comparison with a control. The effect of dry organic solvents on the methanolysis of N-acetyl-L-tyrosine ethyl ester was investigated by high-performance liquid chromatography (HPLC), and it was found that the rate enhancement correlated closely with the hydrophobicity of the solvent.
Department of Advanced Technology Fusion, Konkuk University, Seoul 143-701, Republic of Korea.
Heylin
H
Park
Seunho
S
Jung
D000596:Amino Acids / Q000737:chemistry*; D002384:Catalysis; D004952:Esters; D000432:Methanol / Q000737:chemistry*; D009844:Oligosaccharides / Q000737:chemistry*; D016962:Sinorhizobium meliloti / Q000737:chemistry*; D012997:Solvents
D000596:Amino Acids; D004952:Esters; D009844:Oligosaccharides; D012997:Solvents; D000432:Methanol