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Structural insights into substrate recognition in proton-dependent oligopeptide transporters.

ABSTRACT: Short-chain peptides are transported across membranes through promiscuous proton-dependent oligopeptide transporters (POTs)--a subfamily of the major facilitator superfamily (MFS). The human POTs, PEPT1 and PEPT2, are also involved in the absorption of various drugs in the gut as well as transport to target cells. Here, we present a structure of an oligomeric POT transporter from Shewanella oneidensis (PepTSo2), which was crystallized in the inward open conformation in complex with the peptidomimetic alafosfalin. All ligand-binding residues are highly conserved and the structural insights presented here are therefore likely to also apply to human POTs.

SUBMITTER: Guettou F

PROVIDER: S-EPMC3790050 | biostudies-literature | 2013 Sep

REPOSITORIES: biostudies-literature

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Structural insights into substrate recognition in proton-dependent oligopeptide transporters.

Guettou Fatma F Quistgaard Esben M EM Trésaugues Lionel L Moberg Per P Jegerschöld Caroline C Zhu Lin L Jong Agnes Jin Oi AJ Nordlund Pär P Löw Christian C

EMBO reports 20130719 9

Short-chain peptides are transported across membranes through promiscuous proton-dependent oligopeptide transporters (POTs)--a subfamily of the major facilitator superfamily (MFS). The human POTs, PEPT1 and PEPT2, are also involved in the absorption of various drugs in the gut as well as transport to target cells. Here, we present a structure of an oligomeric POT transporter from Shewanella oneidensis (PepTSo2), which was crystallized in the inward open conformation in complex with the peptidomi ...[more]

PMID: 23867627

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