Dataset Information

The type VII secretion system protects Staphylococcus aureus against host-specific fatty acids

ABSTRACT: The Staphylococcus aureus type VII secretion system (T7SS) exports several proteins that are pivotal for bacterial virulence. The mechanisms underlying T7SS-mediated staphylococcal survival during infection are nevertheless unclear. Here we show that EsxC, a small secreted effector implicated in bacterial persistence, contributes to S. aureus membrane architecture and fluidity. Interestingly, isogenic mutants lacking EsxC, T7SS effectors (EsxA or EsxB), and the membrane-bound EssC are more sensitive to killing by the host-specific fatty acid, linoleic acid (LA), compared to the wild-type. We demonstrate that LA induces more cell membrane damage in the T7SS mutants, although they do not bind differentially to LA. Membrane lipid profiles show that T7SS mutants are also less able to incorporate LA into their membrane phospholipids. Proteomics analyses of wild-type and mutant cell fractions reveal that, in addition to compromising membranes, T7SS defects readily induce bacterial stress and hamper their response to LA challenge. Together, our findings indicate that T7SS is crucial for S. aureus membrane integrity and homeostasis, which is critical when bacteria encounter antimicrobial fatty acids.

INSTRUMENT(S): Orbitrap Fusion ETD

ORGANISM(S): Staphylococcus Aureus

SUBMITTER: Andrew Bottrill

LAB HEAD: Meera Unnikrishnan

PROVIDER: PXD013081 | Pride | 2021-09-08

REPOSITORIES: Pride

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			Action	DRS
	Experiment MS17-185 Arnaud_JE2_DESXC1 from OT_171012_95_MS17-185_Kengmo_JE2_DESXC1.mzid_Experiment_MS17-185_Arnaud_JE2_DESXC1_from_OT_171012_95_MS17-185_Kengmo_JE2_DESXC1.pride.mgf.gz	Mzid
	Experiment MS17-185 Arnaud_JE2_DESXC1 from OT_171012_95_MS17-185_Kengmo_JE2_DESXC1.pride.mztab.gz	Mztab
	Experiment MS17-185 Arnaud_JE2_DESXC2 from OT_171012_95_MS17-185_Kengmo_JE2_DESXC2.mzid_Experiment_MS17-185_Arnaud_JE2_DESXC2_from_OT_171012_95_MS17-185_Kengmo_JE2_DESXC2.pride.mgf.gz	Mzid
	Experiment MS17-185 Arnaud_JE2_DESXC2 from OT_171012_95_MS17-185_Kengmo_JE2_DESXC2.pride.mztab.gz	Mztab
	Experiment MS17-185 Arnaud_JE2_DESXC3 from OT_171012_95_MS17-185_Kengmo_JE2_DESXC3.mzid_Experiment_MS17-185_Arnaud_JE2_DESXC3_from_OT_171012_95_MS17-185_Kengmo_JE2_DESXC3.pride.mgf.gz	Mzid

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The type VII secretion system protects Staphylococcus aureus against antimicrobial host fatty acids.

Kengmo Tchoupa Arnaud A Watkins Kate E KE Jones Rebekah A RA Kuroki Agnès A Alam Mohammad Tauqeer MT Perrier Sebastien S Chen Yin Y Unnikrishnan Meera M

Scientific reports 20200909 1

The Staphylococcus aureus type VII secretion system (T7SS) exports several proteins that are pivotal for bacterial virulence. The mechanisms underlying T7SS-mediated staphylococcal survival during infection nevertheless remain unclear. Here we report that S. aureus lacking T7SS components are more susceptible to host-derived antimicrobial fatty acids. Unsaturated fatty acids such as linoleic acid (LA) elicited an increased inhibition of S. aureus mutants lacking T7SS effectors EsxC, EsxA and Esx ...[more]

PMID: 32908165

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