HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Eliasson, R. Articles by Reichard, P. Search for Related Content PubMed PubMed Citation Articles by Eliasson, R. Articles by Reichard, P. Social Bookmarking                      What's this?

J. Biol. Chem., Vol. 269, Issue 42, 26052-26057, 10, 1994

Allosteric control of the substrate specificity of the anaerobic ribonucleotide reductase from Escherichia coli

R Eliasson, E Pontis, X Sun and P Reichard
Department of Biochemistry 1, Medical Nobel Institute, Karolinska Institutet, Stockholm, Sweden.

The reduction of ribonucleotides is catalyzed by different enzymes in aerobic and anaerobic Escherichia coli, each with a different primary and quaternary structure. Here, we describe the allosteric regulation of the substrate specificity of the anaerobic ribonucleoside triphosphate reductase. The enzyme reduced ribonucleotides at a low basal rate. Reduction was stimulated up to 10-fold by an appropriate modulator (dGTP for ATP reduction, ATP for CTP and UTP reduction, and dTTP for GTP reduction). dGTP and dTTP inhibited the reduction of the "incorrect" substrate; dATP inhibited reduction of all four. From kinetic, effector binding, and competition experiments we conclude that the enzyme has two classes of sites, one that binds ATP and dATP and regulates pyrimidine ribonucleotide reduction ("pyrimidine site"), the other that binds dATP, dGTP, and dTTP and regulates purine ribonucleotide reduction ("purine site"). This model differs slightly from the model for the aerobic reductase, but the physiological consequences remain the same and explain how a single enzyme can provide a balanced supply of the four dNTPs. The similarity of a highly sophisticated control mechanism for the aerobic and anaerobic enzymes suggests that both arose by divergent evolution from a common ancestor, in spite of their different structures.
CiteULike    Complore    Connotea    Del.icio.us    Digg    Reddit    Technorati    What's this?

This article has been cited by other articles:

				E. Torrents, G. Buist, A. Liu, R. Eliasson, J. Kok, I. Gibert, A. Graslund, and P. Reichard The Anaerobic (Class III) Ribonucleotide Reductase from Lactococcus lactis. CATALYTIC PROPERTIES AND ALLOSTERIC REGULATION OF THE PURE ENZYME SYSTEM J. Biol. Chem., January 28, 2000; 275(4): 2463 - 2471. [Abstract] [Full Text] [PDF]

				J. Tamarit, E. Mulliez, C. Meier, A. Trautwein, and M. Fontecave The Anaerobic Ribonucleotide Reductase from Escherichia coli. THE SMALL PROTEIN IS AN ACTIVATING ENZYME CONTAINING A [4Fe-4S]2+ CENTER J. Biol. Chem., October 29, 1999; 274(44): 31291 - 31296. [Abstract] [Full Text] [PDF]

				R. Eliasson, E. Pontis, A. Jordan, and P. Reichard Allosteric Control of Three B12-dependent (Class II) Ribonucleotide Reductases. IMPLICATIONS FOR THE EVOLUTION OF RIBONUCLEOTIDE REDUCTION J. Biol. Chem., March 12, 1999; 274(11): 7182 - 7189. [Abstract] [Full Text] [PDF]

				A. Hofer, J. T. Ekanem, and L. Thelander Allosteric Regulation of Trypanosoma brucei Ribonucleotide Reductase Studied in Vitro and in Vivo J. Biol. Chem., December 18, 1998; 273(51): 34098 - 34104. [Abstract] [Full Text] [PDF]

				M. C. Olcott, J. Andersson, and B.-M. Sjoberg Localization and Characterization of Two Nucleotide-binding Sites on the Anaerobic Ribonucleotide Reductase from Bacteriophage T4 J. Biol. Chem., September 18, 1998; 273(38): 24853 - 24860. [Abstract] [Full Text] [PDF]

				A. Hofer, P. P. Schmidt, A. Graslund, and L. Thelander Cloning and characterization of the R1 and R2 subunits of ribonucleotide reductase from Trypanosoma brucei PNAS, June 24, 1997; 94(13): 6959 - 6964. [Abstract] [Full Text] [PDF]

				J. Riera, F. T. Robb, R. Weiss, and M. Fontecave Ribonucleotide reductase in the archaeon Pyrococcus furiosus: A critical enzyme in the evolution of DNA genomes? PNAS, January 21, 1997; 94(2): 475 - 478. [Abstract] [Full Text] [PDF]

				R. Eliasson, E. Pontis, A. Jordan, and P. Reichard Allosteric Regulation of the Third Ribonucleotide Reductase (NrdEF Enzyme) from Enterobacteriaceae J. Biol. Chem., October 25, 1996; 271(43): 26582 - 26587. [Abstract] [Full Text] [PDF]

				X. Sun, S. Ollagnier, P. P. Schmidt, M. Atta, E. Mulliez, L. Lepape, R. Eliasson, A. Gräslund, M. Fontecave, P. Reichard, et al. The Free Radical of the Anaerobic Ribonucleotide Reductase from Escherichia coli Is at Glycine 681 J. Biol. Chem., March 22, 1996; 271(12): 6827 - 6831. [Abstract] [Full Text] [PDF]

				J. Andersson, M. Westman, A. Hofer, and B.-M. Sjoberg Allosteric Regulation of the Class III Anaerobic Ribonucleotide Reductase from Bacteriophage T4 J. Biol. Chem., June 23, 2000; 275(26): 19443 - 19448. [Abstract] [Full Text] [PDF]

				P. Reichard, R. Eliasson, R. Ingemarson, and L. Thelander Cross-talk between the Allosteric Effector-binding Sites in Mouse Ribonucleotide Reductase J. Biol. Chem., October 13, 2000; 275(42): 33021 - 33026. [Abstract] [Full Text] [PDF]

				J. Andersson, S. Bodevin, M. Westman, M. Sahlin, and B.-M. Sjoberg Two Active Site Asparagines Are Essential for the Reaction Mechanism of the Class III Anaerobic Ribonucleotide Reductase from Bacteriophage T4 J. Biol. Chem., October 26, 2001; 276(44): 40457 - 40463. [Abstract] [Full Text] [PDF]