Identification and quantification of alpha-amino adipic acid in bovine dentine phosphoprotein.
A unique phosphoprotein, which contains an uncommon amino acid, alpha-amino adipic acid (alpha-AAA), was isolated from unerupted bovine teeth by extensive EDTA demineralization. The alpha-AAA in the protein hydrolysates was identified based on the elution time on an amino acid analyzer using the sodium and lithium citrate buffer in a dual column system, and its identity was confirmed by comparisons of its DNS derivative with that of authentic alpha-AAA. This result suggests that the lysine residues in the phosphoprotein may be deaminated by an amine oxidase into allysine and further oxidized to alpha-AAA.
D015074:2-Aminoadipic Acid / Q000032:analysis*; D000596:Amino Acids / Q000032:analysis; D000600:Amino Acids, Dicarboxylic / Q000032:analysis*; D000818:Animals; D002417:Cattle; D002855:Chromatography, Thin Layer; D003804:Dentin / Q000032:analysis*; D010750:Phosphoproteins / Q000032:analysis*; D014097:Tooth, Unerupted / Q000032:analysis
D000596:Amino Acids; D000600:Amino Acids, Dicarboxylic; D010750:Phosphoproteins; D015074:2-Aminoadipic Acid