Dataset Information

Outer membrane utilisomes mediate oligosaccharide uptake in gut Bacteroidetes

ABSTRACT: Bacteroidetes are abundant members of the human microbiota, and species occupying the distal gut are capable of utilising a myriad of diet- and host-derived glycans. Transport of glycans across the outer membrane (OM) of these bacteria is mediated by SusCD protein complexes. Additionally, cell surface-exposed lipoproteins, namely surface glycan binding proteins and glycoside hydrolases, play critical roles in the capture and processing of large glycan chains into transport-competent substrates. Here we show that, for the levan and dextran utilisation systems of Bacteroides thetaiotaomicron, the additional OM components assemble on the core SusCD transporter, forming stable glycan utilising machines which we term ‘utilisomes’. Single particle electron cryogenic electron microscopy (cryo-EM) structures in the absence and presence of substrate reveal concerted conformational changes that rationalise the role of each component for efficient nutrient capture, as well as providing a direct demonstration of the pedal bin mechanism of substrate capture in the intact utilisome.

INSTRUMENT(S): Orbitrap Fusion Lumos

ORGANISM(S): Bacteroides Thetaiotaomicron Bacteria

SUBMITTER: Matthias Trost

LAB HEAD: Matthias Trost

PROVIDER: PXD034863 | Pride | 2023-06-19

REPOSITORIES: Pride

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Dataset's files

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			Action	DRS
	20201017_TH_BvdB_Bt_Mem_01.raw	Raw
	20201017_TH_BvdB_Bt_Mem_02.raw	Raw
	20201017_TH_BvdB_Bt_Mem_03.raw	Raw
	20210210_TH_BvdB_Bt_Mem_condition_2_01.raw	Raw
	20210210_TH_BvdB_Bt_Mem_condition_2_02.raw	Raw

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Publications

Outer membrane utilisomes mediate glycan uptake in gut Bacteroidetes.

White Joshua B R JBR Silale Augustinas A Feasey Matthew M Heunis Tiaan T Zhu Yiling Y Zheng Hong H Gajbhiye Akshada A Firbank Susan S Baslé Arnaud A Trost Matthias M Bolam David N DN van den Berg Bert B Ranson Neil A NA

Nature 20230607 7965

Bacteroidetes are abundant members of the human microbiota, utilizing a myriad of diet- and host-derived glycans in the distal gut<sup>1</sup>. Glycan uptake across the bacterial outer membrane of these bacteria is mediated by SusCD protein complexes, comprising a membrane-embedded barrel and a lipoprotein lid, which is thought to open and close to facilitate substrate binding and transport. However, surface-exposed glycan-binding proteins and glycoside hydrolases also play critical roles in the ...[more]

PMID: 37286596

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