Biosynthesis of the peptidoglycan of bacterial cell walls. XI. Formation of the isoglutamine amide group in the cell walls of Staphylococcus aureus.

The lipid intermediates in peptidoglycan synthesis in Sfaphylococcus aureus, N-acetyhuuramyl(-pentapeptide)-PP-lipid and N-acetylglucosaminyl-N-acetyhnuramyl(-pentapeptide)-P-P-lipid, act as acceptors of ammonia in an ATP-dependent reaction in which the ar-carboxyl group of glutamic acid is amidated. Procedures have been developed for the separation of the amide and the amide-free forms of the lipid intermediates, and it has been shown that the amide-free lipid intermediate can substitute for the uridine nucleotide substrates in the amidation reaction. Some properties of the reaction are reported.