The enzyme, characterized from the bacterium Xanthomonas oryzae, catalyses the ligation of a terminal L-glutamate to UDP-N-acetyl-alpha-D-muramoyl-L-alanine. The combined activity of this enzyme and EC 5.1.1.23, UDP-N-acetyl-alpha-D-muramoyl-L-alanyl-L-glutamate epimerase, provides an alternative route for incorporating D-glutamate into peptidoglycan, replacing the more common combination of EC 5.1.1.3, glutamate racemase, and EC 6.3.2.9, UDP-N-acetylmuramoyl-L-alanine---D-glutamate ligase.