1KVM

X-ray Crystal Structure of AmpC WT beta-Lactamase in Complex with Covalently Bound Cephalothin

Summary for 1KVM

• Entry DOI: 10.2210/pdb1kvm/pdb
• Related: 1KE4 1KVL 2BLS
• Descriptor: beta-lactamase, PHOSPHATE ION, 5-METHYLENE-2-[2-OXO-1-(2-THIOPHEN-2-YL-ACETYLAMINO)-ETHYL]-5,6-DIHYDRO-2H-[1,3]THIAZINE-4-CARBOXYLIC ACID, ... (4 entities in total)
• Functional Keywords: amide hydrolase, beta-lactamase, cephalothin, acyl-enzyme complex, hydrolase
• Biological source: Escherichia coli
• Cellular location: Periplasm: P00811
• Total number of polymer chains: 2
• Total formula weight: 79609.22

Authors

Beadle, B.M.,Trehan, I.,Focia, P.J.,Shoichet, B.K. (deposition date: 2002-01-27, release date: 2002-03-13, Last modification date: 2024-10-09)

Primary citation

Beadle, B.M.,Trehan, I.,Focia, P.J.,Shoichet, B.K.
Structural milestones in the reaction pathway of an amide hydrolase: substrate, acyl, and product complexes of cephalothin with AmpC beta-lactamase.
Structure, 10:413-424, 2002

PubMed Abstract: Beta-lactamases hydrolyze beta-lactam antibiotics and are the leading cause of bacterial resistance to these drugs. Although beta-lactamases have been extensively studied, structures of the substrate-enzyme and product-enzyme complexes have proven elusive. Here, the structure of a mutant AmpC in complex with the beta-lactam cephalothin in its substrate and product forms was determined by X-ray crystallography to 1.53 A resolution. The acyl-enzyme intermediate between AmpC and cephalothin was determined to 2.06 A resolution. The ligand undergoes a dramatic conformational change as the reaction progresses, with the characteristic six-membered dihydrothiazine ring of cephalothin rotating by 109 degrees. These structures correspond to all three intermediates along the reaction path and provide insight into substrate recognition, catalysis, and product expulsion.

PubMed: 12005439
DOI: 10.1016/S0969-2126(02)00725-6

Experimental method

X-RAY DIFFRACTION (2.06 Å)