Information on EC - ribonucleoside-triphosphate reductase (thioredoxin)

for references in articles please use BRENDA:EC1.17.4.2
Please wait a moment until all data is loaded. This message will disappear when all data is loaded.
EC Tree
IUBMB Comments
The enzyme, characterized from the bacterium Lactobacillus leichmannii, is similar to class II ribonucleoside-diphosphate reductase (cf. EC However, it is specific for the triphosphate versions of its substrates. The enzyme contains an adenosylcobalamin cofactor that is involved in generation of a transient thiyl (sulfanyl) radical on a cysteine residue. This radical attacks the substrate, forming a ribonucleotide 3'-radical, followed by water loss to form a ketyl (alpha-oxoalkyl) radical. The ketyl radical is reduced to 3'-keto-deoxynucleotide concomitant with formation of a disulfide anion radical between two cysteine residues. A proton-coupled electron-transfer from the disulfide radical to the substrate generates a 3'-deoxynucleotide radical, and the final product is formed when the hydrogen atom that was initially removed from the 3'-position of the nucleotide by the thiyl radical is returned to the same position. The disulfide bridge is reduced by the action of thioredoxin. cf. EC, ribonucleoside-triphosphate reductase (formate).
Specify your search results
Select one or more organisms in this record: ?
Word Map
The enzyme appears in viruses and cellular organisms
2'-deoxyribonucleoside-triphosphate:oxidized-thioredoxin 2'-oxidoreductase, adenosylcobalamin-dependent ribonucleoside-triphosphate reductase, class Ib ribonucleotide reductase, class Ib RNR, class II ribonucleotide reductase, class II RNR, class III ribonucleotide reductase, class III RNR, More, nrdD, more
2'-deoxyribonucleoside 5'-triphosphate + thioredoxin disulfide + H2O = ribonucleoside 5'-triphosphate + thioredoxin
show the reaction diagram
requires a cobamide coenzyme and ATP
Select items on the left to see more content.