BIOMAT Database Logo BIOMAT Database Logo

The active form of the R2F protein of class Ib ribonucleotide reductase from Corynebacterium ammoniagenes is a diferric protein. 2000

Y Huque, and F Fieschi, and E Torrents, and I Gibert, and R Eliasson, and P Reichard, and M Sahlin, and B M Sjoberg
Department of Molecular Biology, Arrhenius Laboratories, Stockholm University, Sweden.

Corynebacterium ammoniagenes contains a ribonucleotide reductase (RNR) of the class Ib type. The small subunit (R2F) of the enzyme has been proposed to contain a manganese center instead of the dinuclear iron center, which in other class I RNRs is adjacent to the essential tyrosyl radical. The nrdF gene of C. ammoniagenes, coding for the R2F component, was cloned in an inducible Escherichia coli expression vector and overproduced under three different conditions: in manganese-supplemented medium, in iron-supplemented medium, and in medium without addition of metal ions. A prominent typical tyrosyl radical EPR signal was observed in cells grown in rich medium. Iron-supplemented medium enhanced the amount of tyrosyl radical, whereas cells grown in manganese-supplemented medium had no such radical. In highly purified R2F protein, enzyme activity was found to correlate with tyrosyl radical content, which in turn correlated with iron content. Similar results were obtained for the R2F protein of Salmonella typhimurium class Ib RNR. The UV-visible spectrum of the C. ammoniagenes R2F radical has a sharp 408-nm band. Its EPR signal at g = 2.005 is identical to the signal of S. typhimurium R2F and has a doublet with a splitting of 0.9 millitesla (mT), with additional hyperfine splittings of 0.7 mT. According to X-band EPR at 77-95 K, the inactive manganese form of the C. ammoniagenes R2F has a coupled dinuclear Mn(II) center. Different attempts to chemically oxidize Mn-R2F showed no relation between oxidized manganese and tyrosyl radical formation. Collectively, these results demonstrate that enzymatically active C. ammoniagenes RNR is a generic class Ib enzyme, with a tyrosyl radical and a diferric metal cofactor.

UI MeSH Term Description Entries
D007501 Iron A metallic element with atomic symbol Fe, atomic number 26, and atomic weight 55.85. It is an essential constituent of HEMOGLOBINS; CYTOCHROMES; and IRON-BINDING PROTEINS. It plays a role in cellular redox reactions and in the transport of OXYGEN. Iron-56,Iron 56
D008024 Ligands A molecule that binds to another molecule, used especially to refer to a small molecule that binds specifically to a larger molecule, e.g., an antigen binding to an antibody, a hormone or neurotransmitter binding to a receptor, or a substrate or allosteric effector binding to an enzyme. Ligands are also molecules that donate or accept a pair of electrons to form a coordinate covalent bond with the central metal atom of a coordination complex. (From Dorland, 27th ed) Ligand
D008345 Manganese A trace element with atomic symbol Mn, atomic number 25, and atomic weight 54.94. It is concentrated in cell mitochondria, mostly in the pituitary gland, liver, pancreas, kidney, and bone, influences the synthesis of mucopolysaccharides, stimulates hepatic synthesis of cholesterol and fatty acids, and is a cofactor in many enzymes, including arginase and alkaline phosphatase in the liver. (From AMA Drug Evaluations Annual 1992, p2035)
D010957 Plasmids Extrachromosomal, usually CIRCULAR DNA molecules that are self-replicating and transferable from one organism to another. They are found in a variety of bacterial, archaeal, fungal, algal, and plant species. They are used in GENETIC ENGINEERING as CLONING VECTORS. Episomes,Episome,Plasmid
D003001 Cloning, Molecular The insertion of recombinant DNA molecules from prokaryotic and/or eukaryotic sources into a replicating vehicle, such as a plasmid or virus vector, and the introduction of the resultant hybrid molecules into recipient cells without altering the viability of those cells. Molecular Cloning
D003352 Corynebacterium A genus of asporogenous bacteria that is widely distributed in nature. Its organisms appear as straight to slightly curved rods and are known to be human and animal parasites and pathogens.
D004578 Electron Spin Resonance Spectroscopy A technique applicable to the wide variety of substances which exhibit paramagnetism because of the magnetic moments of unpaired electrons. The spectra are useful for detection and identification, for determination of electron structure, for study of interactions between molecules, and for measurement of nuclear spins and moments. (From McGraw-Hill Encyclopedia of Science and Technology, 7th edition) Electron nuclear double resonance (ENDOR) spectroscopy is a variant of the technique which can give enhanced resolution. Electron spin resonance analysis can now be used in vivo, including imaging applications such as MAGNETIC RESONANCE IMAGING. ENDOR,Electron Nuclear Double Resonance,Electron Paramagnetic Resonance,Paramagnetic Resonance,Electron Spin Resonance,Paramagnetic Resonance, Electron,Resonance, Electron Paramagnetic,Resonance, Electron Spin,Resonance, Paramagnetic
D004591 Electrophoresis, Polyacrylamide Gel Electrophoresis in which a polyacrylamide gel is used as the diffusion medium. Polyacrylamide Gel Electrophoresis,SDS-PAGE,Sodium Dodecyl Sulfate-PAGE,Gel Electrophoresis, Polyacrylamide,SDS PAGE,Sodium Dodecyl Sulfate PAGE,Sodium Dodecyl Sulfate-PAGEs
D004926 Escherichia coli A species of gram-negative, facultatively anaerobic, rod-shaped bacteria (GRAM-NEGATIVE FACULTATIVELY ANAEROBIC RODS) commonly found in the lower part of the intestine of warm-blooded animals. It is usually nonpathogenic, but some strains are known to produce DIARRHEA and pyogenic infections. Pathogenic strains (virotypes) are classified by their specific pathogenic mechanisms such as toxins (ENTEROTOXIGENIC ESCHERICHIA COLI), etc. Alkalescens-Dispar Group,Bacillus coli,Bacterium coli,Bacterium coli commune,Diffusely Adherent Escherichia coli,E coli,EAggEC,Enteroaggregative Escherichia coli,Enterococcus coli,Diffusely Adherent E. coli,Enteroaggregative E. coli,Enteroinvasive E. coli,Enteroinvasive Escherichia coli
D001426 Bacterial Proteins Proteins found in any species of bacterium. Bacterial Gene Products,Bacterial Gene Proteins,Gene Products, Bacterial,Bacterial Gene Product,Bacterial Gene Protein,Bacterial Protein,Gene Product, Bacterial,Gene Protein, Bacterial,Gene Proteins, Bacterial,Protein, Bacterial,Proteins, Bacterial

Related Publications

Y Huque, and F Fieschi, and E Torrents, and I Gibert, and R Eliasson, and P Reichard, and M Sahlin, and B M Sjoberg
The manganese-containing ribonucleotide reductase of Corynebacterium ammoniagenes is a class Ib enzyme.
February 1998, The Journal of biological chemistry,
Y Huque, and F Fieschi, and E Torrents, and I Gibert, and R Eliasson, and P Reichard, and M Sahlin, and B M Sjoberg
The class Ib ribonucleotide reductase from Mycobacterium tuberculosis has two active R2F subunits.
August 2014, Journal of biological inorganic chemistry : JBIC : a publication of the Society of Biological Inorganic Chemistry,
Y Huque, and F Fieschi, and E Torrents, and I Gibert, and R Eliasson, and P Reichard, and M Sahlin, and B M Sjoberg
Crystallization and preliminary X-ray analysis of the small subunit (R2F) of native ribonucleotide reductase from Corynebacterium ammoniagenes.
September 2009, Acta crystallographica. Section F, Structural biology and crystallization communications,
Y Huque, and F Fieschi, and E Torrents, and I Gibert, and R Eliasson, and P Reichard, and M Sahlin, and B M Sjoberg
Corynebacterium ammoniagenes class Ib ribonucleotide reductase: transcriptional regulation of an atypical genomic organization in the nrd cluster.
April 2003, Microbiology (Reading, England),
Y Huque, and F Fieschi, and E Torrents, and I Gibert, and R Eliasson, and P Reichard, and M Sahlin, and B M Sjoberg
A tyrosyl-dimanganese coupled spin system is the native metalloradical cofactor of the R2F subunit of the ribonucleotide reductase of Corynebacterium ammoniagenes.
August 2010, Journal of the American Chemical Society,
Y Huque, and F Fieschi, and E Torrents, and I Gibert, and R Eliasson, and P Reichard, and M Sahlin, and B M Sjoberg
Crystal structure of the di-iron/radical protein of ribonucleotide reductase from Corynebacterium ammoniagenes.
January 2002, Biochemistry,
Y Huque, and F Fieschi, and E Torrents, and I Gibert, and R Eliasson, and P Reichard, and M Sahlin, and B M Sjoberg
Crystal structure of the biologically active form of class Ib ribonucleotide reductase small subunit from Mycobacterium tuberculosis.
July 2004, FEBS letters,
Y Huque, and F Fieschi, and E Torrents, and I Gibert, and R Eliasson, and P Reichard, and M Sahlin, and B M Sjoberg
NrdI, a flavodoxin involved in maintenance of the diferric-tyrosyl radical cofactor in Escherichia coli class Ib ribonucleotide reductase.
September 2008, Proceedings of the National Academy of Sciences of the United States of America,
Y Huque, and F Fieschi, and E Torrents, and I Gibert, and R Eliasson, and P Reichard, and M Sahlin, and B M Sjoberg
Ribonucleotide reductase of Brevibacterium ammoniagenes is a manganese enzyme.
January 1988, European journal of biochemistry,
Y Huque, and F Fieschi, and E Torrents, and I Gibert, and R Eliasson, and P Reichard, and M Sahlin, and B M Sjoberg
Orientation of the tyrosyl radical in Salmonella typhimurium class Ib ribonucleotide reductase determined by high field EPR of R2F single crystals.
October 2006, The Journal of biological chemistry,
Copied contents to your clipboard!