The Composition of the Spore Wall and the Wall of Vegetative Cells of Bacillus subtilis

Abstract

SUMMARY: The spore wall of Bacillus subtilis is composed largely of structural protein, in contrast to the peptide+amino sugar + sugar complex of the wall of vegetative cells. Alanine, glutamic acid, α ε-diaminopimelic acid, glucosamine, muramic acid, glucose, ribitol compounds and O-ester groups are the principal constituents of the vegetative cell walls. All of the compounds characteristic of the peptide+amino sugar+sugar complex have been detected in the spore wall preparations but they account only for a minor part of the spore wall. The walls of the vegetative bacteria have a high phosphorus content and contain appreciable amounts of a ribitol phosphate polymer. Spore walls and vegetative cell walls differ also in the nature of their N-terminal amino acids; glycine is the principal N-terminal amino acid of the spore wall protein whereas alanine is the main amino acid found in the wall of vegetative cells.