Dataset Information

Dynamics of an LPS translocon induced by substrate and an antimicrobial peptide

ABSTRACT: We investigated the conformational dynamics of the LPS translocon LptDE was using hydrogen-deuterium exchange mass spectrometry. We evaluated the conformational changes of LptDE upon binding of LPS, Re-LPS (an LPS substructure), thanatin, and the membrane lipid POPG. Our data reveal that LPS induces opening of the LptD β-taco domain, coupled with conformational changes on β-strands adjacent to the putative lateral exit gate. Conversely, an antimicrobial peptide, thanatin, stabilises the β-taco, thus blocking these conformational fluctuations and preventing LPS transport. Our results illustrate that LPS insertion into the OM relies on concerted opening movements of both β-barrel and β-taco domains.

INSTRUMENT(S): SYNAPT G2-Si

ORGANISM(S): Klebsiella Pneumoniae

SUBMITTER: Francesco Fiorentino

LAB HEAD: Carol V. Robinson

PROVIDER: PXD021743 | Pride | 2020-11-16

REPOSITORIES: Pride

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Dynamics of an LPS translocon induced by substrate and an antimicrobial peptide.

Fiorentino Francesco F Sauer Joshua B JB Qiu Xingyu X Corey Robin A RA Cassidy C Keith CK Mynors-Wallis Benjamin B Mehmood Shahid S Bolla Jani R JR Stansfeld Phillip J PJ Robinson Carol V CV

Nature chemical biology 20201116 2

Lipopolysaccharide (LPS) transport to the outer membrane (OM) is a crucial step in the biogenesis of microbial surface defenses. Although many features of the translocation mechanism have been elucidated, molecular details of LPS insertion via the LPS transport (Lpt) OM protein LptDE remain elusive. Here, we integrate native MS with hydrogen-deuterium exchange MS and molecular dynamics simulations to investigate the influence of substrate and peptide binding on the conformational dynamics of Lpt ...[more]

PMID: 33199913

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			Action	DRS
	Apo.zip	Other
	HDXDatatables.zip	Other
	LPS.zip	Other
	LPSThanatin.zip	Other
	POPG.zip	Other