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Title: Crystallization of a newly discovered histidine acid phosphatase from Francisella tularensis

Abstract

A histidine acid phosphatase from the CDC Category A pathogen F. tularensis has been crystallized in space group P4{sub 1}2{sub 1}2, with unit-cell parameters a = 61.96, c = 210.78 Å. A 1.75 Å resolution data set was collected at Advanced Light Source beamline 4.2.2. Francisella tularensis is a highly infectious bacterial pathogen that is considered by the Centers for Disease Control and Prevention to be a potential bioterrorism weapon. Here, the crystallization of a 37.2 kDa phosphatase encoded by the genome of F. tularensis subsp. holarctica live vaccine strain is reported. This enzyme shares 41% amino-acid sequence identity with Legionella pneumophila major acid phosphatase and contains the RHGXRXP motif that is characteristic of the histidine acid phosphatase family. Large diffraction-quality crystals were grown in the presence of Tacsimate, HEPES and PEG 3350. The crystals belong to space group P4{sub 1}2{sub 1}2, with unit-cell parameters a = 61.96, c = 210.78 Å. The asymmetric unit is predicted to contain one protein molecule, with a solvent content of 53%. A 1.75 Å resolution native data set was recorded at beamline 4.2.2 of the Lawrence Berkeley National Laboratory Advanced Light Source. Molecular-replacement trials using the human prostatic acid phosphatase structure as themore » search model (28% amino-acid sequence identity) did not produce a satisfactory solution. Therefore, the structure of F. tularensis histidine acid phosphatase will be determined by multiwavelength anomalous dispersion phasing using a selenomethionyl derivative.« less

Authors:
 [1];  [2];  [3];  [2];  [1];  [3]
  1. Department of Chemistry, University of Missouri-Columbia, Columbia, Missouri 65211 (United States)
  2. Department of Veterinary Pathobiology, College of Veterinary Medicine, University of Missouri-Columbia, Columbia, Missouri 65212 (United States)
  3. (United States)
Publication Date:
OSTI Identifier:
22356247
Resource Type:
Journal Article
Resource Relation:
Journal Name: Acta Crystallographica. Section F; Journal Volume: 62; Journal Issue: Pt 1; Other Information: PMCID: PMC2150932; PMID: 16511256; PUBLISHER-ID: ll5042; OAI: oai:pubmedcentral.nih.gov:2150932; Copyright (c) International Union of Crystallography 2006; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United Kingdom
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; CRYSTALLIZATION; CRYSTALS; DIFFRACTION; HISTIDINE; MATHEMATICAL SOLUTIONS; MOLECULES; POTENTIALS; RESOLUTION; SOLUTIONS; SOLVENTS; SPACE GROUPS; STRAINS

Citation Formats

Felts, Richard L., Reilly, Thomas J., Veterinary Medical Diagnostic Laboratory, College of Veterinary Medicine, University of Missouri-Columbia, Columbia, Missouri 65212, Calcutt, Michael J., Tanner, John J., E-mail: tannerjj@missouri.edu, and Department of Biochemistry, University of Missouri-Columbia, Columbia, Missouri 65211. Crystallization of a newly discovered histidine acid phosphatase from Francisella tularensis. United Kingdom: N. p., 2006. Web. doi:10.1107/S1744309105039813.
Felts, Richard L., Reilly, Thomas J., Veterinary Medical Diagnostic Laboratory, College of Veterinary Medicine, University of Missouri-Columbia, Columbia, Missouri 65212, Calcutt, Michael J., Tanner, John J., E-mail: tannerjj@missouri.edu, & Department of Biochemistry, University of Missouri-Columbia, Columbia, Missouri 65211. Crystallization of a newly discovered histidine acid phosphatase from Francisella tularensis. United Kingdom. doi:10.1107/S1744309105039813.
Felts, Richard L., Reilly, Thomas J., Veterinary Medical Diagnostic Laboratory, College of Veterinary Medicine, University of Missouri-Columbia, Columbia, Missouri 65212, Calcutt, Michael J., Tanner, John J., E-mail: tannerjj@missouri.edu, and Department of Biochemistry, University of Missouri-Columbia, Columbia, Missouri 65211. Sun . "Crystallization of a newly discovered histidine acid phosphatase from Francisella tularensis". United Kingdom. doi:10.1107/S1744309105039813.
@article{osti_22356247,
title = {Crystallization of a newly discovered histidine acid phosphatase from Francisella tularensis},
author = {Felts, Richard L. and Reilly, Thomas J. and Veterinary Medical Diagnostic Laboratory, College of Veterinary Medicine, University of Missouri-Columbia, Columbia, Missouri 65212 and Calcutt, Michael J. and Tanner, John J., E-mail: tannerjj@missouri.edu and Department of Biochemistry, University of Missouri-Columbia, Columbia, Missouri 65211},
abstractNote = {A histidine acid phosphatase from the CDC Category A pathogen F. tularensis has been crystallized in space group P4{sub 1}2{sub 1}2, with unit-cell parameters a = 61.96, c = 210.78 Å. A 1.75 Å resolution data set was collected at Advanced Light Source beamline 4.2.2. Francisella tularensis is a highly infectious bacterial pathogen that is considered by the Centers for Disease Control and Prevention to be a potential bioterrorism weapon. Here, the crystallization of a 37.2 kDa phosphatase encoded by the genome of F. tularensis subsp. holarctica live vaccine strain is reported. This enzyme shares 41% amino-acid sequence identity with Legionella pneumophila major acid phosphatase and contains the RHGXRXP motif that is characteristic of the histidine acid phosphatase family. Large diffraction-quality crystals were grown in the presence of Tacsimate, HEPES and PEG 3350. The crystals belong to space group P4{sub 1}2{sub 1}2, with unit-cell parameters a = 61.96, c = 210.78 Å. The asymmetric unit is predicted to contain one protein molecule, with a solvent content of 53%. A 1.75 Å resolution native data set was recorded at beamline 4.2.2 of the Lawrence Berkeley National Laboratory Advanced Light Source. Molecular-replacement trials using the human prostatic acid phosphatase structure as the search model (28% amino-acid sequence identity) did not produce a satisfactory solution. Therefore, the structure of F. tularensis histidine acid phosphatase will be determined by multiwavelength anomalous dispersion phasing using a selenomethionyl derivative.},
doi = {10.1107/S1744309105039813},
journal = {Acta Crystallographica. Section F},
number = Pt 1,
volume = 62,
place = {United Kingdom},
year = {Sun Jan 01 00:00:00 EST 2006},
month = {Sun Jan 01 00:00:00 EST 2006}
}
  • Histidine acid phosphatases catalyze the transfer of a phosphoryl group from phosphomonoesters to water at acidic pH using an active-site histidine. The histidine acid phosphatase from the category A pathogen Francisella tularensis (FtHAP) has been implicated in intramacrophage survival and virulence, motivating interest in understanding the structure and mechanism of this enzyme. Here, we report a structure-based study of ligand recognition by FtHAP. The 1.70-{angstrom}-resolution structure of FtHAP complexed with the competitive inhibitor L(+)-tartrate was solved using single-wavelength anomalous diffraction phasing. Structures of the ligand-free enzyme and the complex with inorganic phosphate were determined at resolutions of 1.85 and 1.70more » {angstrom}, respectively. The structure of the Asp261Ala mutant enzyme complexed with the substrate 3'-AMP was determined at 1.50 {angstrom} resolution to gain insight into substrate recognition. FtHAP exhibits a two-domain fold similar to that of human prostatic acid phosphatase, consisting of an {alpha}/{beta} core domain and a smaller domain that caps the core domain. The structures show that the core domain supplies the phosphoryl binding site, catalytic histidine (His17), and an aspartic acid residue (Asp261) that protonates the leaving group, while the cap domain contributes residues that enforce substrate preference. FtHAP and human prostatic acid phosphatase differ in the orientation of the crucial first helix of the cap domain, implying differences in the substrate preferences of the two enzymes. 3'-AMP binds in one end of a 15-{angstrom}-long tunnel, with the adenine clamped between Phe23 and Tyr135, and the ribose 2'-hydroxyl interacting with Gln132. The importance of the clamp is confirmed with site-directed mutagenesis; mutation of Phe23 and Tyr135 individually to Ala increases K{sub m} by factors of 7 and 10, respectively. The structural data are consistent with a role for FtHAP in scavenging phosphate from small molecules present in host macrophage cells.« less
  • Francisella tularensis, a potential bioweapon, causes a rare infectious disease called tularemia in humans and animals. The macrophage growth locus A (MglA) protein from F. tularensis associates with RNA polymerase to positively regulate the expression of multiple virulence factors that are required for its survival and replication within macrophages. The MglA protein was overproduced in Escherichia coli, purified and crystallized. The crystals diffracted to 7.5 {angstrom} resolution at the Advanced Photon Source, Argonne National Laboratory and belonged to the hexagonal space group P6{sub 1} or P6{sub 5}, with unit-cell parameters a = b = 125, c = 54 {angstrom}.
  • Francisella tularensis is a highly virulent and contagious Gram-negative intracellular bacterium that causes the disease tularemia in mammals. The high infectivity and the ability of the bacterium to survive for weeks in a cool, moist environment have raised the possibility that this organism could be exploited deliberately as a potential biological weapon. Fatty acid biosynthesis (FAS-II) is essential for bacterial viability and has been validated as a target for the discovery of novel antibacterials. The FAS-II enoyl reductase ftuFabI has been cloned and expressed, and a series of diphenyl ethers have been identified that are subnanomolar inhibitors of the enzymemore » with MIC90 values as low as 0.00018 ?g mL-1. The existence of a linear correlation between the Ki and MIC values strongly suggests that the antibacterial activity of the diphenyl ethers results from direct inhibition of ftuFabI within the cell. The compounds are slow-onset inhibitors of ftuFabI, and the residence time of the inhibitors on the enzyme correlates with their in vivo activity in a mouse model of tularemia infection. Significantly, the rate of breakdown of the enzyme-inhibitor complex is a better predictor of in vivo activity than the overall thermodynamic stability of the complex, a concept that has important implications for the discovery of novel chemotherapeutics that normally rely on equilibrium measurements of potency.« less
  • Francisella tularensis causes the zoonosis tularemia in humans and is one of the most virulent bacterial pathogens. We utilized a global proteomic approach to characterize protein changes in bronchoalveolar lavage fluid from mice exposed to one of three organisms, F. tularensis ssp. novicida, an avirulent mutant of F. tularensis ssp. novicida (F.t. novicida-ΔmglA); and Pseudomonas aeruginosa. The composition of BALF proteins was altered following infection, including proteins involved in neutrophil activation, oxidative stress and inflammatory responses. Components of the innate immune response were induced including the acute phase response and the complement system, however the timing of their induction varied.more » Francisella tularensis ssp. novicida infected mice do not appear to have an effective innate immune response in the first hours of infection, however within 24 hours they show an upregulation of innate immune response proteins. This delayed response is in contrast to P. aeruginosa infected animals which show an early innate immune response. Likewise, F.t. novicida-ΔmglA infection initiates an early innate immune response, however this response is dimished by 24 hours. Finally, this study identifies several candidate biomarkers, including Chitinase 3-like-1 (CHI3L1 or YKL-40) and peroxiredoxin 1, that are associated with F. tularensis ssp. novicida but not P. aeruginosa infection.« less