Peptic hydrolysis of ovalbumin modified by acetylation,

Abstract

1. 1. Two types of acetylated ovalbumin derivatives designated as N-and N,O-acetylovalbumin were prepared by treatment with ketene at pH's 5.6 and 9.0, respectively.2. 2. Both limited and extensive acetylation decreases the digestibility of ovalbumin by crystalline pepsin.3. 3. The limited digestion of the N,O-acetylovalbumin may be attributed to three influences: the acetyl groups on the seven amino groups unsubstituted in the N-acetyl derivative, those on the tyrosyl residues, and those in unidentified positions, rather than to any one of these.4. 4. The results are in agreement with the view that pepsin is of broad specificity toward protein substrates.