Nonenzymatic Galactosylation of Human Serum Albumin. In Vitro Preparation

Authors

Joseph C. Urbanowski, University of Rhode Island
Menashi A. Cohenford
Joel A. Dain, University of Rhode IslandFollow

Document Type

Article

Date of Original Version

1982

Department

Biochemistry

Abstract

Incubation of purified human serum albumin with D-[1-¹⁴C]galactose (5 mM) or D-[1-¹⁴C]glucose (5 mM) in vitro for 7 days under physiological conditions resulted in the time-dependent accumulation of radioactivity into trichloroacetic acid-precipitable material. Comparative studies indicated that the rate of sugar incorporation into albumin increased with increasing pH and temperature of incubation and followed a first order dependence with regard to monosaccharide and albumin concentrations. The extent of nonenzymatic galactosylation of human albumin was approximately 300% greater than the extent of nonenzymatic glucosylation under equivalent experimental conditions. Prolonged dialysis of the modified albumins against a large excess of the unlabeled monosaccharides failed to alter the amount of protein-bound radiolabeled carbohydrate, suggesting that the linkage between sugar and albumin is covalent in nature. The post-translational modification of proteins by nonenzymatic galactosylation may be of physiological significance in individuals with reduced galactokinase or galactose-1-phosphate uridyl transferase activities.

Citation/Publisher Attribution

Urbanowski, J. C., Cohenford, M. A., & Dain, J. A. (1982). Nonenzymatic Galactosylation of Human Serum Albumin. In Vitro Preparatio. Journal of Biological Chemistry, 257(1), 111-115. Retrieved from http://www.jbc.org/content/257/1/111.

Available at: http://www.jbc.org/content/257/1/111