Proteomic Analysis of Arginine Adducts on Glyoxal-modified Ribonuclease

• Published in: Molecular & cellular proteomics Vol. 3; no. 12; pp. 1145 - 1153
• Main Authors: Cotham, William E, Metz, Thomas O, Ferguson, P Lee, Brock, Jonathan W C, Hinton, Davinia J S, Thorpe, Suzanne R, Baynes, John W, Ames, Jennifer M
• Format: Journal Article
• Language: English
• Published: United States American Society for Biochemistry and Molecular Biology 01-12-2004
• Subjects: Amino Acids - chemistry; Animals; Arginine - chemistry; Binding Sites; Cattle; Chromatography; Chromatography, High Pressure Liquid; Dithiothreitol - pharmacology; Glyoxal - chemistry; Imidazoles - chemistry; Kinetics; Models, Chemical; Peptides - chemistry; Ribonucleases - chemistry; Spectrometry, Mass, Electrospray Ionization; Time Factors; Trypsin - chemistry; Trypsin - pharmacology
• ISSN: 1535-9476; 1535-9484; 1535-9484
• DOI: 10.1074/mcp.M400002-MCP200

Accumulation of advanced glycation end-products (AGEs) on proteins is associated with the development of diabetic complications.
Although the overall extent of modification of protein by AGEs is limited, localization of these modifications at a few critical
sites might have a significant effect on protein structure and function. In the present study, we describe the sites of modification
of RNase by glyoxal under physiological conditions. Arg 39 and Arg 85 , which are closest to the active site of the enzyme, were identified as the primary sites of formation of the glyoxal-derived
dihydroxyimidazolidine and hydroimidazolone adducts. Lower amounts of modification were detected at Arg 10 , while Arg 33 appeared to be unmodified. We conclude that dihydroxyimidazolidine adducts are the primary products of modification of protein
by glyoxal, that Arg 39 and Arg 85 are the primary sites of modification of RNase by glyoxal, and that modification of arginine residues during Maillard reactions
of proteins is a highly selective process.