2bq1
From Proteopedia
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==Overview== | ==Overview== | ||
| - | Ribonucleotide reductase is an indispensable enzyme for all cells, since | + | Ribonucleotide reductase is an indispensable enzyme for all cells, since it catalyses the biosynthesis of the precursors necessary for both building and repairing DNA. The ribonucleotide reductase class I enzymes, present in all mammals as well as in many prokaryotes and DNA viruses, are composed mostly of two homodimeric proteins, R1 and R2. The reaction involves long-range radical transfer between the two proteins. Here, we present the first crystal structure of a ribonucleotide reductase R1/R2 holocomplex. The biological relevance of this complex is based on the binding of the R2 C terminus in the hydrophobic cleft of R1, an interaction proven to be crucial for enzyme activity, and by the fact that all conserved amino acid residues in R2 are facing the R1 active sites. We suggest that the asymmetric R1/R2 complex observed in the 4A crystal structure of Salmonella typhimurium ribonucleotide reductase represents an intermediate stage in the reaction cycle, and at the moment of reaction the homodimers transiently form a tight symmetric complex. |
==About this Structure== | ==About this Structure== | ||
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[[Category: ribonucleotide reductase]] | [[Category: ribonucleotide reductase]] | ||
| - | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 16:40:24 2008'' |
Revision as of 14:40, 21 February 2008
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RIBONUCLEOTIDE REDUCTASE CLASS 1B HOLOCOMPLEX R1E,R2F FROM SALMONELLA TYPHIMURIUM
Overview
Ribonucleotide reductase is an indispensable enzyme for all cells, since it catalyses the biosynthesis of the precursors necessary for both building and repairing DNA. The ribonucleotide reductase class I enzymes, present in all mammals as well as in many prokaryotes and DNA viruses, are composed mostly of two homodimeric proteins, R1 and R2. The reaction involves long-range radical transfer between the two proteins. Here, we present the first crystal structure of a ribonucleotide reductase R1/R2 holocomplex. The biological relevance of this complex is based on the binding of the R2 C terminus in the hydrophobic cleft of R1, an interaction proven to be crucial for enzyme activity, and by the fact that all conserved amino acid residues in R2 are facing the R1 active sites. We suggest that the asymmetric R1/R2 complex observed in the 4A crystal structure of Salmonella typhimurium ribonucleotide reductase represents an intermediate stage in the reaction cycle, and at the moment of reaction the homodimers transiently form a tight symmetric complex.
About this Structure
2BQ1 is a Protein complex structure of sequences from Salmonella typhimurium with , and as ligands. Active as Ribonucleoside-diphosphate reductase, with EC number 1.17.4.1 Known structural/functional Site: . Full crystallographic information is available from OCA.
Reference
The first holocomplex structure of ribonucleotide reductase gives new insight into its mechanism of action., Uppsten M, Farnegardh M, Domkin V, Uhlin U, J Mol Biol. 2006 Jun 2;359(2):365-77. Epub 2006 Mar 31. PMID:16631785
Page seeded by OCA on Thu Feb 21 16:40:24 2008
Categories: Protein complex | Ribonucleoside-diphosphate reductase | Salmonella typhimurium | Domkin, V. | Farnegardh, M. | Uhlin, U. | Uppsten, M. | DGT | FE | MG | Allosteric enzyme | Allosteric regulation | Asymmetric complex | Atp-binding | Class 1b | Dna replication | Holocomplex | Iron | Metal-binding | Nucleotide-binding | Oxidoreductase | R1 | R1e | R2 | R2f | Radical transfer | Ribonucleotide reductase
