Sialyltransferase activity in normal and atherosclerotic human aorta intima

• Published in: Biochemistry (Moscow) Vol. 66; no. 4; pp. 397 - 401
• Main Authors: Gracheva, E V, Samovilova, N N, Golovanova, N K, Il'inskaya, O P, Tararak, E M, Prokazova, N V
• Format: Journal Article
• Language: English
• Published: United States Springer Nature B.V 01-04-2001
• Subjects: Adult; Aged; Aorta - enzymology; Arteriosclerosis - enzymology; Enzyme Activation - physiology; Enzymes; Female; Humans; In Vitro Techniques; Kinetics; Male; Membrane Glycoproteins - analysis; Membrane Glycoproteins - isolation & purification; Membrane Glycoproteins - metabolism; Membranes; Reference Values; Sialyltransferases - analysis; Sialyltransferases - isolation & purification; Sialyltransferases - metabolism; Tissues; Tunica Intima - enzymology
• ISSN: 0006-2979; 1608-3040
• DOI: 10.1023/A:1010245328209

Sialyltransferase activity has been determined in Golgi membrane fractions isolated from atherosclerotic and normal intima of human aorta by measuring the transfer of N-acetylneuraminic acid (NeuAc) from CMP-NeuAc to asialofetuin. The asialofetuin-sialyltransferase activity was found to be twofold higher in the atherosclerotic intima than in the normal intima. The mean value of the apparent Michaelis constant (Km) for the sialylating enzyme in both tissues did not differ and was 57 microM. In contrast, the maximal velocity (Vmax) was 2-fold higher for the atherosclerotic intima than for the normal intima. These results suggest that expression of asialofetuin-sialyltransferases of the aortal intima may be increased in atherosclerosis.