THE SITE OF BINDING OF PYRIDOXAL-5′-PHOSPHATE TO HEAR GLUTAMIC-ASPARTIC TRANSAMINASE

Abstract
A tetradecapeptide containing covalently bound pyridoxyl-5[image]-phosphate has been isolated from pig heart glutamic-aspartic transaminase after reduction with sodium borohydride and subsequent degradation with chymotrypsin. A partial structure for the peptide has been shown to be Ser. Thr. Glu. (Asp, Gly, Ala, Val. Ileu, [epsilon]-pyridoxyllys, Lys) Gly. Ser. Asp. Phe. The significance of the results, together with similar information as to the site of binding of the vitamin derivative to muscle phosphorylase [alpha], is discussed.