Abstract
In order to elucidate the significance of amino groups as active groups of lysozyme, egg white lysozyme was acetylated with acetic anhydride. The acetylated lysozyme was fractionated by CM-cellulose column chromatography. All acetylated lysozymes fraction-ated exhibited 120% relative activity toward glycol chitin at pH 5.6, while the optimum pH shifted to the alkaline side by 0.5 pH units. Trinitrophenylated lysozyme, which was derived from acetylated lysozyme with 1.1 free amino groups per mole and which contained no amino group itself, retained 75% relative activity toward glycol chitin. These results indicate that the amino groups in the lysozyme molecule are not involved in the active site.
Acetylated lysozyme behaved the same as the untreated enzyme except the suscepti-bility to proteolytic digestion.
