3so7

Publication Abstract from PubMed

OpdA is a binuclear metalloenzyme that can hydrolyze organophosphate pesticides and nerve agents. In this study the crystal structure of the complex between OpdA and phosphate has been determined to 2.20A resolution. The structure shows the phosphate bound in a tripodal mode to the metal ions whereby two of the oxygen atoms of PO(4) are terminally bound to each metal ion and a third oxygen bridges the two metal ions, thus displacing the muOH in the active site. In silico modelling demonstrates that the phosphate moiety of a reaction product, e.g. diethyl phosphate, may bind in the same orientation, positioning the diethyl groups neatly into the substrate binding pocket close to the metal center. Thus, similar to the binuclear metallohydrolases urease and purple acid phosphatase the tripodal arrangement of PO(4) is interpreted in terms of a role of the muOH as a reaction nucleophile.

Phosphate-bound structure of an organophosphate-degrading enzyme from Agrobacterium radiobacter.,Ely F, Pedroso MM, Gahan LR, Ollis DL, Guddat LW, Schenk G J Inorg Biochem. 2012 Jan;106(1):19-22. Epub 2011 Sep 17. PMID:22112835^[1]

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.