Several authors are improperly using the terms 'glucosylated (or glycosylated) hemoglobin', 'protein glucosylation (or glycosylation)', etc. to refer to the products of nonenzymic reactions between glucose or other sugars and free amino groups of proteins. The compounds so formed are not glycosides, however, but result from the formation of a Schiff's base followed by an Amadori rearrangement. For example, the product of the reaction between glucose and hemoglobin is not glucosylated hemoglobin but an amino linked 1-deoxyfructose derivative of hemoglobin. We suggest the term 'glycation' for any reaction that links a sugar to a protein, whether it is catalysed by an enzyme or not. Thus glycation includes glycosylation as a special case. The product of glycation is a glycated protein, or, in the particular case of the reaction with hemoglobin, glycated hemoglobin.
1. IUPAC-IUB Joint Commission on Biochemical Nomenclature (JCBN), and Nomenclature Commission of IUB (NC-IUB),.Newsletter 1984, Arch. Biochem. Biophys., 1984, 229, 237-245; Biochem. Internat., 1984, 8, following p 202; Biochem. J., 1984, 217, I-IV; Biosci. Rep., 1984, 4, 177-180; Chem. Internat., 1984(3), 24-25; Eur. J. Biochem., 1984, 138, 5-7; Hoppe-Seyler's Z. Physiol. Chem., 1984, 365, I-IV; Trends Biochem. Sci., 1984, 9, various issues.