5UVN

Structure of E. coli MCE protein PqiB, periplasmic domain

Summary for 5UVN

• Entry DOI: 10.2210/pdb5uvn/pdb
• Related: 5UW2 5UW8 5UWA
• EMDB information: 8608 8611 8612
• Descriptor: Paraquat-inducible protein B (1 entity in total)
• Functional Keywords: mce protein, bacterial lipid transport, transport protein
• Biological source: Escherichia coli; More
• Total number of polymer chains: 6
• Total formula weight: 293142.26

Authors

Bhabha, G.,Ekiert, D.C. (deposition date: 2017-02-20, release date: 2017-04-12, Last modification date: 2024-03-13)

Primary citation

Ekiert, D.C.,Bhabha, G.,Isom, G.L.,Greenan, G.,Ovchinnikov, S.,Henderson, I.R.,Cox, J.S.,Vale, R.D.
Architectures of Lipid Transport Systems for the Bacterial Outer Membrane.
Cell, 169:273-285.e17, 2017

PubMed Abstract: How phospholipids are trafficked between the bacterial inner and outer membranes through the hydrophilic space of the periplasm is not known. We report that members of the mammalian cell entry (MCE) protein family form hexameric assemblies with a central channel capable of mediating lipid transport. The E. coli MCE protein, MlaD, forms a ring associated with an ABC transporter complex in the inner membrane. A soluble lipid-binding protein, MlaC, ferries lipids between MlaD and an outer membrane protein complex. In contrast, EM structures of two other E. coli MCE proteins show that YebT forms an elongated tube consisting of seven stacked MCE rings, and PqiB adopts a syringe-like architecture. Both YebT and PqiB create channels of sufficient length to span the periplasmic space. This work reveals diverse architectures of highly conserved protein-based channels implicated in the transport of lipids between the membranes of bacteria and some eukaryotic organelles.

PubMed: 28388411
DOI: 10.1016/j.cell.2017.03.019

Experimental method

ELECTRON MICROSCOPY (3.96 Å)