1dra: Difference between revisions
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[[Image:1dra.gif|left|200px]] | [[Image:1dra.gif|left|200px]] | ||
'''CRYSTAL STRUCTURE OF UNLIGANDED ESCHERICHIA COLI DIHYDROFOLATE REDUCTASE. LIGAND-INDUCED CONFORMATIONAL CHANGES AND COOPERATIVITY IN BINDING''' | {{Structure | ||
|PDB= 1dra |SIZE=350|CAPTION= <scene name='initialview01'>1dra</scene>, resolution 1.9Å | |||
|SITE= | |||
|LIGAND= <scene name='pdbligand=CL:CHLORIDE+ION'>CL</scene>, <scene name='pdbligand=CA:CALCIUM+ION'>CA</scene> and <scene name='pdbligand=MTX:METHOTREXATE'>MTX</scene> | |||
|ACTIVITY= [http://en.wikipedia.org/wiki/Dihydrofolate_reductase Dihydrofolate reductase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=1.5.1.3 1.5.1.3] | |||
|GENE= | |||
}} | |||
'''CRYSTAL STRUCTURE OF UNLIGANDED ESCHERICHIA COLI DIHYDROFOLATE REDUCTASE. LIGAND-INDUCED CONFORMATIONAL CHANGES AND COOPERATIVITY IN BINDING''' | |||
==Overview== | ==Overview== | ||
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==About this Structure== | ==About this Structure== | ||
1DRA is a [ | 1DRA is a [[Single protein]] structure of sequence from [http://en.wikipedia.org/wiki/Escherichia_coli Escherichia coli]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1DRA OCA]. | ||
==Reference== | ==Reference== | ||
Crystal structure of unliganded Escherichia coli dihydrofolate reductase. Ligand-induced conformational changes and cooperativity in binding., Bystroff C, Kraut J, Biochemistry. 1991 Feb 26;30(8):2227-39. PMID:[http:// | Crystal structure of unliganded Escherichia coli dihydrofolate reductase. Ligand-induced conformational changes and cooperativity in binding., Bystroff C, Kraut J, Biochemistry. 1991 Feb 26;30(8):2227-39. PMID:[http://www.ncbi.nlm.nih.gov/pubmed/1998681 1998681] | ||
[[Category: Dihydrofolate reductase]] | [[Category: Dihydrofolate reductase]] | ||
[[Category: Escherichia coli]] | [[Category: Escherichia coli]] | ||
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[[Category: oxidoreductase]] | [[Category: oxidoreductase]] | ||
''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Mar 20 10:43:09 2008'' | ||
Revision as of 08:43, 20 March 2008
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| 1dra, resolution 1.9Å | |||||||||||||
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| Ligands: | CL, CA and MTX | ||||||||||||
| Activity: | Dihydrofolate reductase, with EC number 1.5.1.3 | ||||||||||||
| Coordinates: | save as pdb, mmCIF, xml | ||||||||||||
CRYSTAL STRUCTURE OF UNLIGANDED ESCHERICHIA COLI DIHYDROFOLATE REDUCTASE. LIGAND-INDUCED CONFORMATIONAL CHANGES AND COOPERATIVITY IN BINDING
Overview
The crystal structure of unliganded dihydrofolate reductase (DHFR) from Escherichia coli has been solved and refined to an R factor of 19% at 2.3-A resolution in a crystal form that is nonisomorphous with each of the previously reported E. coli DHFR crystal structures [Bolin, J. T., Filman, D. J., Matthews, D. A., Hamlin, B. C., & Kraut, J. (1982) J. Biol. Chem. 257, 13650-13662; Bystroff, C., Oatley, S. J., & Kraut, J. (1990) Biochemistry 29, 3263-3277]. Significant conformational changes occur between the apoenzyme and each of the complexes: the NADP+ holoenzyme, the folate-NADP+ ternary complex, and the methotrexate (MTX) binary complex. The changes are small, with the largest about 3 A and most of them less than 1 A. For simplicity a two-domain description is adopted in which one domain contains the NADP+ 2'-phosphate binding site and the binding sites for the rest of the coenzyme and for the substrate lie between the two domains. Binding of either NADP+ or MTX induces a closing of the PABG-binding cleft and realignment of alpha-helices C and F which bind the pyrophosphate of the coenzyme. Formation of the ternary complex from the holoenzyme does not involve further relative domain shifts but does involve a shift of alpha-helix B and a floppy loop (the Met-20 loop) that precedes alpha B. These observations suggest a mechanism for cooperativity in binding between substrate and coenzyme wherein the greatest degree of cooperativity is expressed in the transition-state complex. We explore the idea that the MTX binary complex in some ways resembles the transition-state complex.
About this Structure
1DRA is a Single protein structure of sequence from Escherichia coli. Full crystallographic information is available from OCA.
Reference
Crystal structure of unliganded Escherichia coli dihydrofolate reductase. Ligand-induced conformational changes and cooperativity in binding., Bystroff C, Kraut J, Biochemistry. 1991 Feb 26;30(8):2227-39. PMID:1998681
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