To improve security and privacy, we are moving our web pages and services from HTTP to HTTPS.
To give users of web services time to transition to HTTPS, we will support separate HTTP and HTTPS services until the end of 2017.
From January 2018 most HTTP traffic will be automatically redirected to HTTPS. [more...]
View this page in https

ENZYME entry: EC

Accepted Name
Ribonucleoside-triphosphate reductase (thioredoxin).
Alternative Name(s)
Ribonucleotide reductase.
Reaction catalysed
2'-deoxyribonucleoside triphosphate + thioredoxin disulfide + H(2)O <=> ribonucleoside triphosphate + thioredoxin
  • 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-oxoacyl) 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 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
PRIAM enzyme-specific profiles1.17.4.2
KEGG Ligand Database for Enzyme Nomenclature1.17.4.2
IUBMB Enzyme Nomenclature1.17.4.2
MEDLINEFind literature relating to
Q035U1, RTPR_LACP3;  A6Q367, RTPR_NITSB;  Q857H2, VG50_BPMB2;  
O64240, VG50_BPMD2;  Q05262, VG50_BPML5;  

View entry in original ENZYME format
View entry in raw text format (no links)

All UniProtKB/Swiss-Prot entries referenced in this entry, with possibility to download in different formats, align etc.
All ENZYME / UniProtKB/Swiss-Prot entries corresponding to 1.17.4.-
All ENZYME / UniProtKB/Swiss-Prot entries corresponding to 1.17.-.-
All ENZYME / UniProtKB/Swiss-Prot entries corresponding to 1.-.-.-