The Dimanganese(II) Site of Bacillus subtilis Class Ib Ribonucleotide Reductase
- MIT
Class Ib ribonucleotide reductases (RNRs) use a dimanganese-tyrosyl radical cofactor, Mn{sub 2}{sup III}-Y{sm_bullet}, in their homodimeric NrdF ({beta}2) subunit to initiate reduction of ribonucleotides to deoxyribonucleotides. The structure of the Mn{sub 2}{sup II} form of NrdF is an important component in understanding O{sub 2}-mediated formation of the active metallocofactor, a subject of much interest because a unique flavodoxin, NrdI, is required for cofactor assembly. Biochemical studies and sequence alignments suggest that NrdF and NrdI proteins diverge into three phylogenetically distinct groups. The only crystal structure to date of a NrdF with a fully ordered and occupied dimanganese site is that of Escherichia coli Mn{sub 2}{sup II}-NrdF, prototypical of the enzymes from actinobacteria and proteobacteria. Here we report the 1.9 {angstrom} resolution crystal structure of Bacillus subtilis Mn{sub 2}{sup II}-NrdF, representative of the enzymes from a second group, from Bacillus and Staphylococcus. The structures of the metal clusters in the {beta}2 dimer are distinct from those observed in E. coli Mn{sub 2}{sup II}-NrdF. These differences illustrate the key role that solvent molecules and protein residues in the second coordination sphere of the Mn{sub 2}{sup II} cluster play in determining conformations of carboxylate residues at the metal sites and demonstrate that diverse coordination geometries are capable of serving as starting points for Mn{sub 2}{sup III}-Y{sm_bullet} cofactor assembly in class Ib RNRs.
- Research Organization:
- Advanced Photon Source (APS), Argonne National Laboratory (ANL), Argonne, IL (US)
- Sponsoring Organization:
- OTHERNIH
- OSTI ID:
- 1047906
- Journal Information:
- Biochemistry-US, Journal Name: Biochemistry-US Journal Issue: (18) ; 05, 2012 Vol. 51; ISSN 0006-2960; ISSN BICHAW
- Country of Publication:
- United States
- Language:
- ENGLISH
Similar Records
Structural Basis for Activation of Class Ib Ribonucleotide Reductase
Metal-free class Ie ribonucleotide reductase from pathogens initiates catalysis with a tyrosine-derived dihydroxyphenylalanine radical
Structural Basis for Superoxide Activation of Flavobacterium johnsoniae Class I Ribonucleotide Reductase and for Radical Initiation by Its Dimanganese Cofactor
Journal Article
·
Thu Dec 02 23:00:00 EST 2010
· Science
·
OSTI ID:1002710
Metal-free class Ie ribonucleotide reductase from pathogens initiates catalysis with a tyrosine-derived dihydroxyphenylalanine radical
Journal Article
·
Sun Sep 16 20:00:00 EDT 2018
· Proceedings of the National Academy of Sciences of the United States of America
·
OSTI ID:1499708
Structural Basis for Superoxide Activation of Flavobacterium johnsoniae Class I Ribonucleotide Reductase and for Radical Initiation by Its Dimanganese Cofactor
Journal Article
·
Sun Apr 01 20:00:00 EDT 2018
· Biochemistry
·
OSTI ID:1499749