ATP cone

In molecular biology, the ATP-cone is an evolutionarily mobile, ATP-binding regulatory domain which is found in a variety of proteins including ribonucleotide reductases, phosphoglycerate kinases and transcriptional regulators.^[1]

ATP-cone
ribonucleotide reductase e441q mutant r1 protein from escherichia coli
Identifiers
Symbol	ATP-cone
Pfam	PF03477
InterPro	IPR005144
SCOP2	7r1r / SCOPe / SUPFAM
Available protein structures: Pfam   structures / ECOD   PDB RCSB PDB; PDBe; PDBj PDBsum structure summary

In ribonucleotide reductase protein R1 from Escherichia coli this domain is located at the N terminus, and is composed mostly of helices.^[2] It forms part of the allosteric effector region and contains the general allosteric activity site in a cleft located at the tip of the N-terminal region.^[3] This site binds either ATP (activating) or dATP (inhibitory), with the base bound in a hydrophobic pocket and the phosphates bound to basic residues. Substrate binding to this site is thought to affect enzyme activity by altering the relative positions of the two subunits of ribonucleotide reductase.

The ATP-cone domain also is a key part of NrdR, that controls transcription of ribonucleotide reductases in bacteria, in response to ATP and dATP levels. ^[4]