Dataset Information

Time series and steady state proteomics of Pseudomonas aeruginosa phenazine mutants

ABSTRACT: Microbes in biofilms face the challenge of substrate limitation. In particular, cells in Pseudomonas aeruginosa biofilms growing in the laboratory or during host colonization often become limited for oxygen. Previously we found that phenazines, antibiotics produced by P. aeruginosa, balance the intracellular redox state for cells in biofilms. Here, we show that genes involved in denitrification are induced in phenazine-null (Δphz) mutant biofilms grown under an aerobic atmosphere, even in the absence of nitrate. This finding suggests that resident cells employ a bet-hedging strategy to anticipate the potential availability of nitrate and counterbalance their highly reduced redox state. Consistent with our previous characterization of aerobically-grown colonies supplemented with nitrate, we find that the pathway that is induced in Δphz colonies combines the nitrate reductase activity of the periplasmic enzyme Nap with downstream reduction of nitrite to nitrogen gas catalyzed by the enzymes Nir, Nor, and Nos. This regulatory relationship differs from the denitrification pathway that functions under anaerobic growth with nitrate as the terminal electron acceptor, which depends on the membrane-associated nitrate reductase Nar. We identify sequences in the promoter regions of the nap and nir operons that are required for the effects of phenazines on expression. We also show that specific phenazines have differential effects on nap gene expression. Finally, we provide evidence that individual steps of the denitrification pathway are catalyzed at different depths within aerobically grown biofilms, suggesting metabolic cross-feeding between community subpopulations. (corresponding publication)

INSTRUMENT(S): LTQ Orbitrap Elite

ORGANISM(S): Pseudomonas Aeruginosa Pa14-rn6

SUBMITTER: Christine Vogel

LAB HEAD: Christine Vogel

PROVIDER: PXD008924 | Pride | 2018-10-19

REPOSITORIES: Pride

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Dataset's files

Source:

			Action	DRS
	RAW_PA_Mutants.rar	Other
	RAW_PA_TimeCourse.rar	Other
	SEARCH_PA_Mutants_MQoutput.rar	Other
	SEARCH_PA_TimeCourse_MQoutput.rar	Other

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Publications

Phenazines Regulate Nap-Dependent Denitrification in Pseudomonas aeruginosa Biofilms.

Lin Yu-Cheng YC Sekedat Matthew D MD Cornell William Cole WC Silva Gustavo M GM Okegbe Chinweike C Price-Whelan Alexa A Vogel Christine C Dietrich Lars E P LEP

Journal of bacteriology 20180409 9

Microbes in biofilms face the challenge of substrate limitation. In particular, oxygen often becomes limited for cells in Pseudomonas aeruginosa biofilms growing in the laboratory or during host colonization. Previously we found that phenazines, antibiotics produced by P. aeruginosa, balance the intracellular redox state of cells in biofilms. Here, we show that genes involved in denitrification are induced in phenazine-null (Δphz) mutant biofilms grown under an aerobic atmos ...[more]

PMID: 29463605

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