Dataset Information

A role for PchHI as an ABC transporter in iron acquisition by the siderophore pyochelin in Pseudomonas aeruginosa

ABSTRACT: Iron is an essential nutrient for bacterial growth but poorly bioavailable. To scavenge ferric iron present in their environment, bacteria synthesize and secrete siderophores, small compounds with a high affinity for iron. Pyochelin (PCH) is one of the two siderophores produced by the opportunistic pathogen Pseudomonas aeruginosa. Once having captured a ferric iron, PCH-Fe is imported back into bacteria first by the outer membrane transporter FptA and afterwards by the inner membrane permease FptX. Here using molecular biology, 55Fe uptake assays and LC-MS/MS quantification of PCH in the different bacterial cell fractions, we show that (i) PCH (probably under its PCH-Fe form) is able to rich bacterial periplasm and cytoplasm when both FptA and FptX are expressed, and (ii) that PchHI (a heterodimeric ABC transporter) plays a role in the translocation of siderophore-free iron siderophore-free iron across the inner membrane into the cytoplasm. Consequently, probably the first fraction of PCH-Fe internalized by FptA may be transported further by FptX in the bacterial cytoplasm to activate the transcriptional regulator PchR, regulating the transcription of all genes of the PCH pathway. The further fractions of PCH-Fe transported by FptA may dissociate in the bacterial periplasm by an unknown mechanism, with the siderophore-free iron being transported into the cytoplasm by PchHI.

INSTRUMENT(S): Q Exactive

ORGANISM(S): Pseudomonas Aeruginosa

SUBMITTER: Lauriane Kuhn

LAB HEAD: Isabelle Schalk

PROVIDER: PXD026833 | Pride | 2022-03-15

REPOSITORIES: Pride

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Dataset's files

Source:

			Action	DRS
	2020_S37_BRoche_500ng_DelX-1.mgf	Mgf
	2020_S37_BRoche_500ng_DelX-1.raw	Raw
	2020_S37_BRoche_500ng_DelX-2.mgf	Mgf
	2020_S37_BRoche_500ng_DelX-2.raw	Raw
	2020_S37_BRoche_500ng_DelX-3.mgf	Mgf

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A role for PchHI as the ABC transporter in iron acquisition by the siderophore pyochelin in Pseudomonas aeruginosa.

Roche Béatrice B Garcia-Rivera Mariel A MA Normant Vincent V Kuhn Lauriane L Hammann Philippe P Brönstrup Mark M Mislin Gaëtan L A GLA Schalk Isabelle J IJ

Environmental microbiology 20211018 2

Iron is an essential nutrient for bacterial growth but poorly bioavailable. Bacteria scavenge ferric iron by synthesizing and secreting siderophores, small compounds with a high affinity for iron. Pyochelin (PCH) is one of the two siderophores produced by the opportunistic pathogen Pseudomonas aeruginosa. After capturing a ferric iron molecule, PCH-Fe is imported back into bacteria first by the outer membrane transporter FptA and then by the inner membrane permease FptX. Here, using molecular bi ...[more]

PMID: 34664350

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