J. Riordan, B. Vallée
1967
Citations
1
Influential Citations
48
Citations
Journal
Methods in Enzymology
Abstract
Publisher Summary O -acetyl groups are introduced into the tyrosyl residues of proteins leading to functional consequences. Tyrosyl residues can be acetylated either with acetic anhydride or with N -acetylimidazole. This chapter discusses the procedure and application of O -acetyltyrosine. The experimental procedure involves: acylation, deacetylation, and estimation of O -acetyltyrosyl residues. The O-acyltyrosyl residue undergoes hydrolysis to regenerate the original functional group. This offers a distinct advantage in the use of acylating reagents for the modification of tyrosyl hydroxyl groups in proteins. The estimation of O -acetyltyrosyl residues involves acethydroxamate formation and spectral analysis. O -acetylation of tyrosine produces a characteristic decrease in absorption between 250 and 300 m μ and the molar absorptivity at 275 decreases. Three major applications are (1) site-specific modifications, (2) free and buried tyrosyl residues, and (3) functional buried tyrosyl residues. N- acetylimidazole may be used to determine the number of surface tyrosyl residues of a protein. A number of enzymes are reversibly inactivated by denaturing agents such as urea or guanidinium salts.