Structural Basis for Activation of Class Ib Ribonucleotide Reductase

• DOI: 10.1126/science.1190187
• Publication Date: 2010-08-06T03:13:33Z
• Authors: Amie K. Boal; Joseph A. Cotruvo; JoAnne Stubbe; Amy C. Rosenzweig
• Keywords: Ribonucleotide reductase; Basis (linear algebra); Ribonucleotide

The class Ib ribonucleotide reductase of Escherichia coli can initiate reduction nucleotides to deoxynucleotides with either a Mn(III)2-tyrosyl radical (Y•) or Fe(III)2-Y• cofactor in the NrdF subunit. Whereas self-assemble from Fe(II)2-NrdF and O2, activation Mn(II)2-NrdF requires reduced flavoprotein, NrdI, proposed form oxidant for assembly by O2. crystal structures reported here E. reveal different coordination environments, suggesting distinct initial binding sites oxidants during activation. In complex oxidized continuous channel connects NrdI flavin Mn(II)2 active site. Crystallographic detection putative peroxide this supports mechanism Mn(III)2-Y• assembly.