Primary Citation of Related Structures:   1IOV, 1IOW
PubMed Abstract: 
The crystallographic structure of the D-alanine:D-alanine ligase of the ddlB gene of Escherichia coli complexed with a D-Ala-D-alpha-hydroxybutyrate phosphonate and the structure of the Y216F mutant ligase complexed with a D-Ala-D-Ala phosphinate have been determined to 2 ...
The crystallographic structure of the D-alanine:D-alanine ligase of the ddlB gene of Escherichia coli complexed with a D-Ala-D-alpha-hydroxybutyrate phosphonate and the structure of the Y216F mutant ligase complexed with a D-Ala-D-Ala phosphinate have been determined to 2.2 and 1.9 A resolution, respectively, and refined to R factors of 0.156 and 0.158. In each complex the inhibitor has reacted with ATP to produce ADP and a tight-binding phosphorylated transition state intermediate. Comparison of these two structures with the known crystal structure of the phosphinate intermediate of the wild-type ligase shows no major conformational changes, but B factors indicate differences in mobility of loops covering the binding site. The weaker inhibition of the Y216F mutant by both inhibitors is thought to be due in part to the loss of an interloop hydrogen bond. A similar mechanism may account for poor inhibition of VanA, the homologous D-Ala:D-lactate ligase produced by vancomycin-resistant enterococci.
Related Citations: 
A Common Fold for Peptide Synthetases Cleaving ATP to Adp Fan, C., Moews, P.C., Shi, Y., Walsh, C.T., Knox, J.R. (1995) Proc Natl Acad Sci U S A 92: 1172
Vancomycin Resistance: Structure of D-Alanine:D-Alanine Ligase at 2.3 A Resolution Fan, C., Moews, P.C., Walsh, C.T., Knox, J.R. (1994) Science 266: 439
Organizational Affiliation: 
Department of Molecular and Cell Biology, The University of Connecticut, Storrs 06269-3125, USA.