5im3

Publication Abstract from PubMed

Ribonucleotide reductases (RNRs) reduce ribonucleotides to deoxyribonucleotides. Their overall activity is stimulated by ATP and downregulated by dATP via a genetically mobile ATP cone domain mediating the formation of oligomeric complexes with varying quaternary structures. The crystal structure and solution X-ray scattering data of a novel dATP-induced homotetramer of the Pseudomonas aeruginosa class I RNR reveal the structural bases for its unique properties, namely one ATP cone that binds two dATP molecules and a second one that is non-functional, binding no nucleotides. Mutations in the observed tetramer interface ablate oligomerization and dATP-induced inhibition but not the ability to bind dATP. Sequence analysis shows that the novel type of ATP cone may be widespread in RNRs. The present study supports a scenario in which diverse mechanisms for allosteric activity regulation are gained and lost through acquisition and evolutionary erosion of different types of ATP cone.

Structural Mechanism of Allosteric Activity Regulation in a Ribonucleotide Reductase with Double ATP Cones.,Johansson R, Jonna VR, Kumar R, Nayeri N, Lundin D, Sjoberg BM, Hofer A, Logan DT Structure. 2016 Apr 27. pii: S0969-2126(16)30036-3. doi:, 10.1016/j.str.2016.03.025. PMID:27133024^[1]

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.