This old version of Proteopedia is provided for student assignments while the new version is undergoing repairs. Content and edits done in this old version of Proteopedia after March 1, 2026 will eventually be lost when it is retired in about June of 2026.
Apply for new accounts at the new Proteopedia. Your logins will work in both the old and new versions.
1jgt
From Proteopedia
OCA (Talk | contribs)
(New page: 200px<br /><applet load="1jgt" size="450" color="white" frame="true" align="right" spinBox="true" caption="1jgt, resolution 1.95Å" /> '''CRYSTAL STRUCTURE OF...)
Next diff →
Revision as of 16:07, 20 November 2007
|
CRYSTAL STRUCTURE OF BETA-LACTAM SYNTHETASE
Overview
The enzyme beta-lactam synthetase (beta-LS) catalyzes the formation of the, beta-lactam ring in clavulanic acid, a clinically important beta-lactamase, inhibitor. Whereas the penicillin beta-lactam ring is generated by, isopenicillin N synthase (IPNS) in the presence of ferrous ion and, dioxygen, beta-LS uses ATP and Mg2+ as cofactors. According to sequence, alignments, beta-LS is homologous to class B asparagine synthetases, (AS-Bs), ATP/Mg2+-dependent enzymes that convert aspartic acid to, asparagine. Here we report the first crystal structure of a beta-LS. The, 1.95 A resolution structure of Streptomyces clavuligerus beta-LS provides, a fully resolved view of the active site in which substrate, closely, related ATP analog alpha,beta-methyleneadenosine 5'-triphosphate (AMP-CPP), and a single Mg2+ ion are present. A high degree of substrate, preorganization is observed. Comparison to Escherichia coli AS-B reveals, the evolutionary changes that have taken place in beta-LS that impede, interdomain reaction, which is essential in AS-B, and that accommodate, beta-lactam formation. The structural data provide the opportunity to, alter the synthetic potential of beta-LS, perhaps leading to the creation, of new beta-lactamase inhibitors and beta-lactam antibiotics.
About this Structure
1JGT is a Single protein structure of sequence from Streptomyces clavuligerus with MG, APC, CMA and GOL as ligands. Full crystallographic information is available from OCA.
Reference
Structure of beta-lactam synthetase reveals how to synthesize antibiotics instead of asparagine., Miller MT, Bachmann BO, Townsend CA, Rosenzweig AC, Nat Struct Biol. 2001 Aug;8(8):684-9. PMID:11473258
Page seeded by OCA on Tue Nov 20 18:14:30 2007
