Studies on insect bacteriolytic enzymes-I. Lysozyme in haemolymph of Galleria mellonella and Bombyx mori

Abstract

1. 1. Bacteriolytic activity develops in haemolymph of immature stages of Bomyx mori and Galleria mellonella after injection with microorganisms but not after saline injection. 2. 2. The purified insect lytic enzymes are small basic proteins with properties, such as stability to heat, optima for pH and ionic strength, similar to those of egg white lysozyme, but with specific activities about six times that of lysozyme. 3. 3. The Galleria enzyme releases from bacterial cell walls reducing sugar end groups which were identified as acetylmuramic acid. The properties of the insect proteins permit their classification as mucopeptide N-aacetylmuramyl- hydrolase (E.C. 3.2.1.17).