Deletion of the ferric uptake regulator Fur impairs the in vitro growth and virulence of Actinobacillus pleuropneumoniae.
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ABSTRACT:
SUBMITTER: Jacobsen I
PROVIDER: S-EPMC1111875 | biostudies-literature | 2005 Jun
REPOSITORIES: biostudies-literature
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Deletion of the ferric uptake regulator Fur impairs the in vitro growth and virulence of Actinobacillus pleuropneumoniae.
Jacobsen Ilse I Gerstenberger Jörg J Gruber Achim D AD Bossé Janine T JT Langford Paul R PR Hennig-Pauka Isabel I Meens Jochen J Gerlach Gerald-F GF
Infection and immunity 20050601 6
In order to investigate the role of the ferric uptake regulator Fur in the porcine lung pathogen Actinobacillus pleuropneumoniae, we constructed an isogenic in-frame deletion mutant, A. pleuropneumoniae Deltafur. This mutant showed constitutive expression of transferrin-binding proteins, growth deficiencies in vitro, and reduced virulence in an aerosol infection model. ...[more]
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2016-06-10 | GSE47773 | GEO
Project description:Fur (ferric uptake regulator) is a key bacterial protein that regulates iron acquisition and its storage, and modulates the expression of genes involved in the response to different environmental stresses. Although the protein is involved in several regulation mechanisms, and members of the Fur family have been identified in pathogen organisms, the stability and thermodynamic characterization of a Fur protein have not been described. In this work, the stability, thermodynamics and structure of the functional dimeric Fur A from Anabaena sp. PCC 7119 were studied by using computational methods and different biophysical techniques, namely, circular dichroism, fluorescence, Fourier-transform infrared, and nuclear magnetic resonance spectroscopies. The structure, as monitored by circular dichroism and Fourier-transform infrared, was composed of a 40% of alpha-helix. Chemical-denaturation experiments indicated that Fur A folded via a two-state mechanism, but its conformational stability was small with a value of DeltaG = 5.3 +/- 0.3 kcal mol(-1) at 298 K. Conversely, Fur A was thermally a highly stable protein. The high melting temperature (Tm = 352 +/- 5 K), despite its moderate conformational stability, can be ascribed to its low heat capacity change upon unfolding, DeltaCp, which had a value of 0.8 +/- 0.1 kcal mol(-1) K(-1). This small value is probably due to burial of polar residues in the Fur A structure. This feature can be used for the design of mutants of Fur A with impaired DNA-binding properties.
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