Structural highlights
2jcs is a 2 chain structure with sequence from Drome. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance.
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| Ligands: | , |
| Related: | 1j90, 1oe0, 1ot3, 1zm7, 1zmx |
| Activity: | Deoxynucleoside kinase, with EC number 2.7.1.145 |
| Resources: | FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT |
Function
[DNK_DROME] Deoxyribonucleoside kinase that has a broad specificity phosphorylating thymidine, deoxyadenosine, deoxycytidine and deoxyguanosine. Specificity is higher for pyrimidine nucleosides. Several anti-viral and anti-cancer nucleoside analogs are also efficiently phosphorylated.[1] [2] [3]
Evolutionary Conservation
Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf.
Publication Abstract from PubMed
The catalytic reaction mechanism and binding of substrates was investigated for the multisubstrate Drosophila melanogaster deoxyribonucleoside kinase. Mutation of E52 to D, Q and H plus mutations of R105 to K and H were performed to investigate the proposed catalytic reaction mechanism, in which E52 acts as an initiating base and R105 is thought to stabilize the transition state of the reaction. Mutant enzymes (E52D, E52H and R105H) showed a markedly decreased k(cat), while the catalytic activity of E52Q and R105K was abolished. The E52D mutant was crystallized with its feedback inhibitor dTTP. The backbone conformation remained unchanged, and coordination between D52 and the dTTP-Mg complex was observed. The observed decrease in k(cat) for E52D was most likely due to an increased distance between the catalytic carboxyl group and 5'-OH of deoxythymidine (dThd) or deoxycytidine (dCyd). Mutation of Q81 to N and Y70 to W was carried out to investigate substrate binding. The mutations primarily affected the K(m) values, whereas the k(cat) values were of the same magnitude as for the wild-type. The Y70W mutation made the enzyme lose activity towards purines and negative cooperativity towards dThd and dCyd was observed. The Q81N mutation showed a 200- and 100-fold increase in K(m), whereas k(cat) was decreased five- and twofold for dThd and dCyd, respectively, supporting a role in substrate binding. These observations give insight into the mechanisms of substrate binding and catalysis, which is important for developing novel suicide genes and drugs for use in gene therapy.
Functional studies of active-site mutants from Drosophila melanogaster deoxyribonucleoside kinase. Investigations of the putative catalytic glutamate-arginine pair and of residues responsible for substrate specificity.,Egeblad-Welin L, Sonntag Y, Eklund H, Munch-Petersen B FEBS J. 2007 Mar;274(6):1542-51. PMID:17302737[4]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
References
- ↑ Johansson M, van Rompay AR, Degreve B, Balzarini J, Karlsson A. Cloning and characterization of the multisubstrate deoxyribonucleoside kinase of Drosophila melanogaster. J Biol Chem. 1999 Aug 20;274(34):23814-9. PMID:10446143
- ↑ Munch-Petersen B, Knecht W, Lenz C, Sondergaard L, Piskur J. Functional expression of a multisubstrate deoxyribonucleoside kinase from Drosophila melanogaster and its C-terminal deletion mutants. J Biol Chem. 2000 Mar 3;275(9):6673-9. PMID:10692477
- ↑ Welin M, Skovgaard T, Knecht W, Zhu C, Berenstein D, Munch-Petersen B, Piskur J, Eklund H. Structural basis for the changed substrate specificity of Drosophila melanogaster deoxyribonucleoside kinase mutant N64D. FEBS J. 2005 Jul;272(14):3733-42. PMID:16008571 doi:10.1111/j.1742-4658.2005.04803.x
- ↑ Egeblad-Welin L, Sonntag Y, Eklund H, Munch-Petersen B. Functional studies of active-site mutants from Drosophila melanogaster deoxyribonucleoside kinase. Investigations of the putative catalytic glutamate-arginine pair and of residues responsible for substrate specificity. FEBS J. 2007 Mar;274(6):1542-51. PMID:17302737 doi:http://dx.doi.org/10.1111/j.1742-4658.2007.05701.x
