Affordable Access

Phosphate-bound structure of an organophosphate-degrading enzyme fromAgrobacterium radiobacter

Authors
Journal
Journal of Inorganic Biochemistry
0162-0134
Publisher
Elsevier
Publication Date
Volume
106
Issue
1
Identifiers
DOI: 10.1016/j.jinorgbio.2011.09.015
Keywords
  • Binuclear Metallohydrolases
  • Organophosphate-Degrading Enzymes
  • Phosphotriesterases
  • Catalytic Mechanism
  • X-Ray Crystallography
Disciplines
  • Biology

Abstract

Abstract 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 2.20 Å 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 μOH 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 μOH as a reaction nucleophile.

There are no comments yet on this publication. Be the first to share your thoughts.

Statistics

Seen <100 times
0 Comments