A plasmid-encoded dihydrofolate reductase from trimethoprim-resistant bacteria has a novel D2-symmetric active site.
Narayana, N., Matthews, D.A., Howell, E.E., Nguyen-huu, X.(1995) Nat Struct Biol 2: 1018-1025
- PubMed: 7583655 
- DOI: 10.1038/nsb1195-1018
- Primary Citation of Related Structures:  
1VIE, 1VIF - PubMed Abstract: 
Bacteria expressing R67-plasmid encoded dihydrofolate reductase (R67 DHFR) exhibit high-level resistance to the antibiotic trimethoprim. Native R67 DHFR is a 34,000 M(r) homotetramer which exists in equilibrium with an inactive dimeric form. The structure of native R67 DHFR has now been solved at 1 ...