A plasmid-encoded dihydrofolate reductase from trimethoprim-resistant bacteria has a novel D2-symmetric active site
- PMID: 7583655
- DOI: 10.1038/nsb1195-1018
A plasmid-encoded dihydrofolate reductase from trimethoprim-resistant bacteria has a novel D2-symmetric active site
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 1.7 A resolution and is unrelated to that of chromosomal DHFR. Homotetrameric R67 DHFR has an unusual pore, 25 A in length, passing through the middle of the molecule. Two folate molecules bind asymmetrically within the pore indicating that the enzyme's active site consists of symmetry related binding surfaces from all four identical units.
Similar articles
-
A glutamine 67--> histidine mutation in homotetrameric R67 dihydrofolate reductase results in four mutations per single active site pore and causes substantial substrate and cofactor inhibition.Protein Eng. 1997 Dec;10(12):1415-24. doi: 10.1093/protein/10.12.1415. Protein Eng. 1997. PMID: 9543003
-
Structure of the Q67H mutant of R67 dihydrofolate reductase-NADP+ complex reveals a novel cofactor binding mode.Protein Sci. 2007 Jun;16(6):1063-8. doi: 10.1110/ps.062740907. Epub 2007 May 1. Protein Sci. 2007. PMID: 17473013 Free PMC article.
-
Role of S65, Q67, I68, and Y69 residues in homotetrameric R67 dihydrofolate reductase.Biochemistry. 2001 Sep 25;40(38):11344-52. doi: 10.1021/bi0110544. Biochemistry. 2001. PMID: 11560482
-
Searching sequence space: two different approaches to dihydrofolate reductase catalysis.Chembiochem. 2005 Apr;6(4):590-600. doi: 10.1002/cbic.200400237. Chembiochem. 2005. PMID: 15812782 Review.
-
Trimethoprim resistance; epidemiology and molecular aspects.J Med Microbiol. 1990 Jan;31(1):1-19. doi: 10.1099/00222615-31-1-1. J Med Microbiol. 1990. PMID: 2404123 Review. No abstract available.
Cited by
-
Functional evolution of two subtly different (similar) folds.BMC Struct Biol. 2001;1:5. doi: 10.1186/1472-6807-1-5. Epub 2001 Dec 21. BMC Struct Biol. 2001. PMID: 11782293 Free PMC article.
-
The three-dimensional structure of the RNA-binding domain of ribosomal protein L2; a protein at the peptidyl transferase center of the ribosome.EMBO J. 1999 Mar 15;18(6):1459-67. doi: 10.1093/emboj/18.6.1459. EMBO J. 1999. PMID: 10075918 Free PMC article.
-
Novel crystallization conditions for tandem variant R67 DHFR yield a wild-type crystal structure.Acta Crystallogr Sect F Struct Biol Cryst Commun. 2011 Nov 1;67(Pt 11):1316-22. doi: 10.1107/S1744309111030417. Epub 2011 Oct 25. Acta Crystallogr Sect F Struct Biol Cryst Commun. 2011. PMID: 22102224 Free PMC article.
-
Small Angle Neutron Scattering Studies of R67 Dihydrofolate Reductase, a Tetrameric Protein with Intrinsically Disordered N-Termini.Biochemistry. 2017 Nov 7;56(44):5886-5899. doi: 10.1021/acs.biochem.7b00822. Biochemistry. 2017. PMID: 29020453 Free PMC article.
-
Dramatic acceleration of protein folding by stabilization of a nonnative backbone conformation.Proc Natl Acad Sci U S A. 2004 May 25;101(21):7954-9. doi: 10.1073/pnas.0400550101. Epub 2004 May 17. Proc Natl Acad Sci U S A. 2004. PMID: 15148398 Free PMC article.