2f00
From Proteopedia
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Escherichia coli MurC
Overview
The bacterial cell wall provides essential protection from the external, environment and confers strength and rigidity to counteract internal, osmotic pressure. Without this layer the cell would be easily ruptured and, it is for this reason that biosynthetic pathways leading to the formation, of peptidoglycan have for many years been a prime target for effective, antibiotics. Central to this pathway are four similar ligase enzymes which, add peptide groups to glycan moieties. As part of a program to better, understand the structure-function relationships in these four enzymes, the, crystal structure of Escherichia coli UDP-N-acetylmuramoyl:L-alanine, ligase (MurC) has been determined to 2.6 A resolution. The structure was, solved by multiwavelength anomalous diffraction methods from a single, selenomethionine-substituted crystal and refined to a crystallographic R, factor of 0.212 (R(free) = 0.259). The enzyme has a modular multi-domain, structure very similar to those of other members of the mur family of, ATP-dependent amide-bond ligases. Detailed comparison of these four, enzymes shows that considerable conformational changes are possible. These, changes, together with the recruitment of two different N-terminal, domains, allow this family of enzymes to bind a substrate which is, identical at one end and at the other has the growing peptide tail which, will ultimately become part of the rigid bacterial cell wall. Comparison, of the E. coli and Haemophilus influenzae structures and analysis of the, sequences of known MurC enzymes indicate the presence of a ;dimerization', motif in almost 50% of the MurC enzymes and points to a highly conserved, loop in domain 3 that may play a key role in amino-acid ligand, specificity.
About this Structure
2F00 is a Single protein structure of sequence from Escherichia coli with MG as ligand. Active as UDP-N-acetylmuramate--L-alanine ligase, with EC number 6.3.2.8 Full crystallographic information is available from OCA.
Reference
Structure of Escherichia coli UDP-N-acetylmuramoyl:L-alanine ligase (MurC)., Deva T, Baker EN, Squire CJ, Smith CA, Acta Crystallogr D Biol Crystallogr. 2006 Dec;62(Pt 12):1466-74. Epub 2006, Nov 23. PMID:17139082
Page seeded by OCA on Wed Nov 21 10:15:38 2007
