Substances reacting as hexosamine and as N-acetylhexosamine liberated from bacterial cell walls by lysozyme

Abstract

The reactions of lysozyme digests of the cell walls of Micrococcus lysodeikticus in the Elson-Morgan (hexosamine) and Morgan-Elson (N-acetylhexosamine) tests were examined. The Elson-Morgan reaction given for "hexosamine" is an artifact, since no free amino sugar amino groups could be demonstrated. The amount of color given by lysozmye digests in the N-acetylhexosamine reaction depended upon the pH of the alkaline solution used in the Morgan-Elson test and upon the time of heating. The distribution of wall components among the fractions of cell-wall digests was studied: 20% of the hexosamine appeared as 6-0-(N-acetylglucosaminyl)-N-acetylmuramic acid and 50% as diffusible material in which the amino sugars were bound to amino acids.