Dataset Information

Hypoxia decreases the pathogenicity of Pseudomonas aeruginosa by reducing expression of multiple virulence factors.

ABSTRACT: Hypoxia is a feature of the microenvironment during P. aeruginosa infection in several disease states. We confirm that the pathogenicity of P. aeruginosa derived from sites of acute infection is higher than those derived from sites of chronic infection. Hypoxia attenuated the pathogenicity of acute but not chronic strains implicating a role for hypoxia in controlling virulence. Mass spectrometric analysis revealed reduced expression of multiple virulence factors in hypoxia including exotoxin A, alkaline protease and proteins important in the synthesis of pyoverdine. Inhibition of pyoverdine production by iron supplementation mimicked the effects of hypoxia. Finally, strains of P. aeruginosa which lacks a functional pseudomonas prolyl-hydroxylase domain containing protein (PPHD) do not respond to hypoxia implicating a possible role for PPHD as an oxygen-sensing determinant of pathogenicity. Understanding how hypoxia influences bacterial virulence will identify new targets for anti–infective therapy against P. aeruginosa.

INSTRUMENT(S): Q Exactive

ORGANISM(S): Pseudomonas Aeruginosa Str. E2uos

SUBMITTER: Alex von kriegsheim

LAB HEAD: Alex von Kriegsheim

PROVIDER: PXD004421 | Pride | 2017-06-06

REPOSITORIES: Pride

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Dataset's files

Source:

			Action	DRS
	20150731_Bettina_B244J_H_1_150804000453.raw	Raw
	20150731_Bettina_B244J_H_2.raw	Raw
	20150731_Bettina_B244J_H_3.raw	Raw
	20150731_Bettina_B244J_N.raw	Raw
	20150731_Bettina_B244J_N_150803212122.raw	Raw

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Publications

Hypoxia Reduces the Pathogenicity of Pseudomonas aeruginosa by Decreasing the Expression of Multiple Virulence Factors.

Schaible Bettina B Rodriguez Javier J Garcia Amaya A von Kriegsheim Alexander A McClean Siobhán S Hickey Caitríona C Keogh Ciara E CE Brown Eric E Schaffer Kirsten K Broquet Alexis A Taylor Cormac T CT

The Journal of infectious diseases 20170501 9

Our understanding of how the course of opportunistic bacterial infection is influenced by the microenvironment is limited. We demonstrate that the pathogenicity of Pseudomonas aeruginosa strains derived from acute clinical infections is higher than that of strains derived from chronic infections, where tissues are hypoxic. Exposure to hypoxia attenuated the pathogenicity of strains from acute (but not chronic) infections, implicating a role for hypoxia in regulating bacterial virulence. Mass spe ...[more]

PMID: 28368464

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