Crystal structure of the class D beta-lactamase OXA-10.
Paetzel, M., Danel, F., de Castro, L., Mosimann, S.C., Page, M.G., Strynadka, N.C.(2000) Nat Struct Biol 7: 918-925
- PubMed: 11017203 
- DOI: https://doi.org/10.1038/79688
- Primary Citation of Related Structures:  
1FOF - PubMed Abstract: 
We report the crystal structure of a class D beta-lactamase, the broad spectrum enzyme OXA-10 from Pseudomonas aeruginosa at 2.0 A resolution. There are significant differences between the overall fold observed in this structure and those of the evolutionarily related class A and class C beta-lactamases. Furthermore, the structure suggests the unique, cation mediated formation of a homodimer. Kinetic and hydrodynamic data shows that the dimer is a relevant species in solution and is the more active form of the enzyme. Comparison of the molecular details of the active sites of the class A and class C enzymes with the OXA-10 structure reveals that there is no counterpart in OXA-10 to the residues proposed to act as general bases in either of these enzymes (Glu 166 and Tyr 150, respectively). Our structures of the native and chloride inhibited forms of OXA-10 suggest that the class D enzymes have evolved a distinct catalytic mechanism for beta-lactam hydrolysis. Clinical variants of OXA-10 are also discussed in light of the structure.
Organizational Affiliation: 
Department of Biochemistry and Molecular Biology, University of British Columbia, 2146 Health Sciences Mall, Vancouver, British Columbia, V6T 1Z3, Canada.