Publication Abstract from PubMed
Human dUTPase, essential for DNA integrity, is an important survival factor for cancer cells. We determined the crystal structure of the enzyme:alpha,beta-imino-dUTP:Mg complex and performed equilibrium binding experiments in solution. Ordering of the C-terminus upon the active site induces close juxtaposition of the incoming nucleophile attacker water oxygen and the alpha-phosphorus of the substrate, decreasing their distance below the van der Waals limit. Complex interactions of the C-terminus with both substrate and product were observed via a specifically designed tryptophan sensor, suitable for further detailed kinetic and ligand binding studies. Results explain the key functional role of the C-terminus.
Active site closure facilitates juxtaposition of reactant atoms for initiation of catalysis by human dUTPase.,Varga B, Barabas O, Kovari J, Toth J, Hunyadi-Gulyas E, Klement E, Medzihradszky KF, Tolgyesi F, Fidy J, Vertessy BG FEBS Lett. 2007 Oct 2;581(24):4783-8. Epub 2007 Sep 12. PMID:17880943[1]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
