This model describes the MurC protein in bacterial peptidoglycan (murein) biosynthesis. In a few species (Mycobacterium leprae, the Chlamydia), the amino acid may be L-serine or glycine instead of L-alanine. A related protein, UDP-N-acetylmuramate:L-alanyl-gamma-D-glutamyl-meso-diaminopimelate ligase (murein tripeptide ligase) is described by model TIGR01081. [Cell envelope, Biosynthesis and degradation of murein sacculus and peptidoglycan]