Ribonucleotide reductase is an essential enzyme in all organisms. It provides precursors for DNA synthesis by reducing all four ribonucleotides to deoxyribonucleotides. The overall activity and the substrate specificity of RNR are allosterically regulated by deoxyribonucleoside triphosphates and ATP, thereby providing balanced dNTP pools.
[1] "Genome of the bacterium Streptococcus pneumoniae strain R6."Hoskins J., Alborn W.E. Jr., Arnold J., Blaszczak L.C., Burgett S., DeHoff B.S., Estrem S.T., Fritz L., Fu D.-J., Fuller W., Geringer C., Gilmour R., Glass J.S., Khoja H., Kraft A.R., Lagace