학술논문

Substrate specificity of GM2 and GD3 synthase of Golgi vesicles derived from rat liver.
Document Type
Article
Source
European Journal of Biochemistry. 9/15/87, Vol. 167 Issue 3, p417-424. 8p.
Subject
*GOLGI apparatus
*LIVER
*ANIMAL models in research
*GANGLIOSIDES
*CHROMOGENIC compounds
*GLYCOSPHINGOLIPIDS
*SIALIC acids
*AMINO compounds
Language
ISSN
0014-2956
Abstract
Several GM3 derivatives have been synthesized. Among them were lyso-GM3 derivatives and GM3 analogues with modifications in the sialic acid moiety. They were used as glycolipid acceptors in assays for GM2 and GD3 synthase of rat liver Golgi. Analysis of the resulting enzyme activities and of the reaction products revealed different substrate specificities for GM2 and GD3 synthase although the normal glycolipid acceptor for both transferases is ganglioside GM3. Specificity of GD3 synthase is strongly determined by the substrate's negative charge and the acyl residue in amide bond to the amino group of neuraminic acid, while GM2 synthase reacts quite indifferently to these changes in the sialic moiety of the substrate. Both enzymes seem to be sensitive to the spatial extension at the neuraminic acid's carboxylic group. [ABSTRACT FROM AUTHOR]