The initial obstacle to a detailed kinetic investigation of the mechanism of action of lysozyme is that of finding soluble substrates in which one identifiable bond is hydrolysed. In addition the kinetic analysis should not be complicated by transglycosylation. Conventional substrates for lysozyme, such as cell walls of Micrococcus lysodeikticus, or the oligosaccharide, chitin, are clearly unsuitable for this purpose.