Long-range structural effects in a second-site revertant of a mutant dihydrofolate reductase.Brown, K.A., Howell, E.E., Kraut, J.
(1993) Proc.Natl.Acad.Sci.USA 90: 11753-11756
- PubMed: 8265622
- Primary Citation of Related Structures:
- PubMed Abstract:
- Crystal Structures of Escherichia Coli and Lactobacillus Casei Dihydrofolate Reductase at 1.7 Angstroms Resolution. I. General Features and Binding of Methotrexate
Bolin, J.T.,Filman, D.J.,Matthews, D.A.,Hamlin, R.C.,Kraut, J.
(1982) Biochemistry 257: 13650
- Crystal Structures of Escherichia Coli and Lactobacillus Casei Dihydrofolate Reductase at 1.7 Angstroms Resolution. II. Environment of Bound Nadph and Implications for Catalysis
Filman, D.J.,Bolin, J.T.,Matthews, D.A.,Kraut, J.
(1982) J.Biol.Chem. 257: 13663
- Role of Aspartate 27 of Dihydrofolate Reductase from Escherichia Coli in Interconversion of Active and Inactive Enzyme Conformers and the Binding of Nadph
Appleman, J.R.,Howell, E.E.,Kraut, J.,Blakely, R.L.
(1990) J.Biol.Chem. 265: 5579
- How Do Mutation at Phenylalanine-153 and Isoleucine-155 Partially Suppress the Effects of the Aspartate-27-> Serine Mutation in Escherichia Coli Dihydrofolate Reductase
Dion, A.,Linn, C.E.,Bradrick, T.D.,Georghiou, S.,Howell, E.E.
(1993) Biochemistry 32: 3479
- A Second-Site Mutation at Phenylalanine-137 that Increases Catalytic Efficiency in the Mutant Aspartate-27-> Serine Escherichia Coli Dihydrofolate Reductase
Howell, E.E.,Booth, C.,Farnum, M.,Kraut, J.,Warren, M.S.
(1990) Biochemistry 29: 8561
- Dihydrofolate Reductase from Escherichia Coli: Probing the Role of Aspartate-27 and Phenylalanine-137 in Enzyme Conformation and the Binding of Nadph
Dunn, S.M.,Lanigan, T.M.,Howell, E.E.
(1990) Biochemistry 29: 8569
- Functional Role of Aspartic Acid-27 in Dihydrofolate Reductase Revealed by Mutagenesis
Howell, E.E.,Villafranca, J.E.,Waren, M.S.,Oatley, S.J.,Kraut, J.
(1986) Science 231: 1123
X-ray crystal structures have been determined for a second-site revertant (Asp-27-->Ser, Phe-137-->Ser; D27S/F137S) and both component single-site mutants of Escherichia coli dihydrofolate reductase. The primary D27S mutation, located in the substrat ...
X-ray crystal structures have been determined for a second-site revertant (Asp-27-->Ser, Phe-137-->Ser; D27S/F137S) and both component single-site mutants of Escherichia coli dihydrofolate reductase. The primary D27S mutation, located in the substrate binding pocket, greatly reduces catalytic activity as compared to the wild-type enzyme. The additional F137S mutation, which partially restores catalytic activity, is located on the surface of the molecule, well outside of the catalytic center and approximately 15 A from residue 27. Comparison of kinetic data for the single-site F137S mutant, specifically constructed as a control, and for the double-mutant enzymes indicates that the effects of the F137S and D27S mutations on catalysis are nonadditive. This result suggests that the second-site mutation might mediate its effects through a structural perturbation propagated along the polypeptide backbone. To investigate the mechanism by which the F137S substitution elevates the catalytic activity of D27S we have determined the structure of the D27S/F137S double mutant. We also present a rerefined structure for the original D27S mutant and a preliminary structural interpretation for the F137S single-site mutant. We find that while either single mutant shows little more than a simple side-chain substitution, the double mutant undergoes an extended structural perturbation, which is propagated between these two widely separated sites via the helix alpha B.
Department of Chemistry, University of California at San Diego, La Jolla 92093.