EC Number   |
General Information |
Reference  |
|---|
    1.17.4.2 | more |
Cys290 in class III from bacteriophage T4 are the conserved cysteine residues that are the sites for generation of the thiyl radical |
715085 |
| 1.17.4.2 | more |
the class II RNR reaction involves deoxyadenosyl or cysteinyl radicals and is independent of oxygen. The thiyl radical in class II RNR is believed to be generated directly at the active site using the cofactor 5'-deoxyadenosylcobalamin |
715085 |
| 1.17.4.2 | more |
the class III RNR reaction involves deoxyadenosyl, glycyl, or cysteinyl radicals and requires anaerobic conditions |
715085 |
| 1.17.4.2 | physiological function |
during anaerobic growth, Escherichia coli depends on a class III RNR for the synthesis of deoxyribonucleotides |
715085 |
| 1.17.4.2 | more |
cycling fibroblasts from a patient with a lethal mutation in p53R2 contain a normal amount of mtDNA and show normal growth, ribonucleotide reduction, and deoxynucleoside triphosphate (dNTP) pools. However, when made quiescent by prolonged serum starvation the mutant cells strongly down-regulate ribonucleotide reduction, decrease their dCTP and dGTP pools, and virtually abolish the catabolism of dCTP in substrate cycles. mtDNA is not affected |
715583 |
| 1.17.4.2 | physiological function |
the enzyme is involved in ribonucleotide reduction, that provides deoxynucleotides for nuclear and mitochondrial DNA replication and DNA repair |
715583 |
| 1.17.4.2 | more |
RNRs are allosterically regulated on two levels, overall activity and substrate specificity. The substrate specificity is regulated by the binding of dNTPs to the specificity site, ATP and dATP upregulate the reduction of CDP and UDP, whereas dTTP upregulates GDP reduction and dGTP increases the rate of ADP reduction. This regulation is essential to maintain balanced dNTP pools for DNA synthesis and repairI |
716317 |
| 1.17.4.2 | metabolism |
RNR is the rate-limiting enzyme in deoxyribonucleoside triphosphate, dNTP, biosynthesis |
716377 |
| 1.17.4.2 | more |
high-level overexpression of RNR subunits, Rrm1, Rrm2 and p53R2, separately or in different combinations, in mice does not result in mtDNA copy number elevation. Instead, simultaneous expression of two RNR subunits leads to imbalanced dNTP pools and progressive mtDNA depletion in the skeletal muscle, without mtDNA mutagenesis, overview |
716377 |
| 1.17.4.2 | physiological function |
RNR is the rate-limiting enzyme in deoxyribonucleoside triphosphate, dNTP, biosynthesis, with important roles in nuclear genome maintenance. RNR is also essential for maintenance of mitochondrial DNA in mammals |
716377 |
