Preliminary time-of-flight neutron diffraction study on diisopropyl fluorophosphatase (DFPase) from Loligo vulgaris
- Institute of Biophysical Chemistry, J. W. Goethe University Frankfurt, Max-von-Laue-Strasse 9, D-60438 Frankfurt (Germany)
- Bioscience Division, Los Alamos National Laboratory, Los Alamos, NM 87545 (United States)
Diisopropyl fluorophosphatase (DFPase) effectively hydrolyzes a number of organophosphorus nerve agents, including sarin, cyclohexylsarin, soman and tabun. Neutron diffraction data have been collected from DFPase crystals to 2.2 Å resolution in an effort to gain further insight into the mechanism of this enzyme. The enzyme diisopropyl fluorophosphatase (DFPase) from Loligo vulgaris is capable of decontaminating a wide variety of toxic organophosphorus nerve agents. DFPase is structurally related to a number of enzymes, such as the medically important paraoxonase (PON). In order to investigate the reaction mechanism of this phosphotriesterase and to elucidate the protonation state of the active-site residues, large-sized crystals of DFPase have been prepared for neutron diffraction studies. Available H atoms have been exchanged through vapour diffusion against D{sub 2}O-containing mother liquor in the capillary. A neutron data set has been collected to 2.2 Å resolution on a relatively small (0.43 mm{sup 3}) crystal at the spallation source in Los Alamos. The sample size and asymmetric unit requirements for the feasibility of neutron diffraction studies are summarized.
- OSTI ID:
- 22360253
- Journal Information:
- Acta Crystallographica. Section F, Journal Name: Acta Crystallographica. Section F Journal Issue: Pt 1 Vol. 63; ISSN ACSFCL; ISSN 1744-3091
- Country of Publication:
- United Kingdom
- Language:
- English
Similar Records
Hydrolysis of DFP and the Nerve Agent (S)-Sarin by DFPase Proceeds Along Two Different Reaction Pathways: Implica-tions for Engineering Bioscavengers
Crystal structures of human group-VIIA phospholipase A2 inhibited by organophosphorus nerve agents exhibit non-aged complexes