Reaction: ATP + D-aspartate + [β-GlcNAc-(1→4)-Mur2Ac(oyl-L-Ala-γ-D-Glu-L-Lys-D-Ala-D-Ala)]n = [β-GlcNAc-(1→4)-Mur2Ac(oyl-L-Ala-γ-D-Glu-6-N-(β-D-Asp)-L-Lys-D-Ala-D-Ala)]n + ADP + phosphate
For diagram click here.
Other name(s): Aslfm; UDP-MurNAc-pentapeptide:D-aspartate ligase; D-aspartic acid-activating enzyme
Systematic name: D-aspartate:[β-GlcNAc-(1→4)-Mur2Ac(oyl-L-Ala-γ-D-Glu-L-Lys-D-Ala-D-Ala)]n ligase (ADP-forming)
Comments: This enzyme forms part of the peptidoglycan assembly pathway of Gram-positive bacteria grown in medium containing D-Asp. Normally, the side chains the acylate the 6-amino group of the L-lysine residue contain L-Ala-L-Ala but these amino acids are replaced by D-Asp when D-Asp is included in the medium. Hybrid chains containing L-Ala-D-Asp, L-Ala-L-Ala-D-Asp or D-Asp-L-Ala are not formed [4]. The enzyme belongs in the ATP-grasp protein superfamily [3,4]. The enzyme is highly specific for D-aspartate, as L-aspartate, D-glutamate, D-alanine, D-iso-asparagine and D-malic acid are not substrates [4]. In Enterococcus faecium, the substrate D-aspartate is produced by EC 5.1.1.13, aspartate racemase [4]
Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, CAS registry number:
References:
1. Staudenbauer, W. and Strominger, J.L. Activation of D-aspartic acid for incorporation into peptidoglycan. J. Biol. Chem. 247 (1972) 5095-5102. [PMID: 4262567]
2. Staudenbauer, W., Willoughby, E. and Strominger, J.L. Further studies of the D-aspartic acid-activating enzyme of Streptococcus faecalis and its attachment to the membrane. J. Biol. Chem. 247 (1972) 5289-5296. [PMID: 4626717]
3. Galperin, M.Y. and Koonin, E.V. A diverse superfamily of enzymes with ATP-dependent carboxylate-amine/thiol ligase activity. Protein Sci. 6 (1997) 2639-2643. [PMID: 9416615]
4. Bellais, S., Arthur, M., Dubost, L., Hugonnet, J.E., Gutmann, L., van Heijenoort, J., Legrand, R., Brouard, J.P., Rice, L. and Mainardi, J.L. Aslfm, the D-aspartate ligase responsible for the addition of D-aspartic acid onto the peptidoglycan precursor of Enterococcus faecium. J. Biol. Chem. 281 (2006) 11586-11594. [PMID: 16510449]