46] Acylamino acid-releasing enzyme from rat liver

Abstract

Publisher Summary This chapter discusses an enzyme that releases acylamino acids from acylated amino-terminal positions of a number of peptides and proteins. Hydrolysis rates depend on nature of acyl groups, terminal amino acid sequences, and tertiary structure of acyl protein substrates. The enzyme may be useful for the removal of the N-terminal acylamino acid, from some of the N-terminally blocked peptides and proteins in amino acid sequence analysis. A similar enzyme has been found also in rabbit reticulocytes and acylamino acid-releasing activity exists in many animal tissues. This chapter discusses the enzyme isolated from rat liver. It elaborates on the enzyme activity is assayed by the ninhydrin method using a synthetic substrate, N-acetyl-L-methionyl-L-threonine (Ac-L-Met-L-Thr). The chapter explains the fractionation of the enzyme, its properties such as purity, stability, pH optimum and Km value, Isoelectric point, molecular weight and subunit structure, and activators and inhibitors. The use of Acylamino Acid-Releasing Enzyme for the Sequence Determination of an N-Acetylated Peptide has been discussed.