5L75

A protein structure

Summary for 5L75

• Entry DOI: 10.2210/pdb5l75/pdb
• Descriptor: Lipopolysaccharide ABC transporter, ATP-binding protein LptB, FIG000988: Predicted permease, FIG000906: Predicted Permease, ... (4 entities in total)
• Functional Keywords: gram-negative bacteria, transport protein
• Biological source: Klebsiella pneumoniae IS22; More
• Total number of polymer chains: 4
• Total formula weight: 134293.70

Authors

Dong, C.,Dong, H.,Zhang, Z.,Paterson, N.,Tang, X. (deposition date: 2016-06-01, release date: 2017-08-16, Last modification date: 2024-05-08)

Primary citation

Dong, H.,Zhang, Z.,Tang, X.,Paterson, N.G.,Dong, C.
Structural and functional insights into the lipopolysaccharide ABC transporter LptB2FG.
Nat Commun, 8:222-222, 2017

PubMed Abstract: The cell surface of most Gram-negative bacteria contains lipopolysaccharide that is essential for their viability and drug resistance. A 134-kDa protein complex LptBFG is unique among ATP-binding cassette transporters because it extracts lipopolysaccharide from the external leaflet of the inner membrane and propels it along a filament that extends across the periplasm to directly deliver lipopolysaccharide into the external leaflet of the outer membrane. Here we report the crystal structure of the lipopolysaccharide transporter LptBFG from Klebsiella pneumoniae, in which both LptF and LptG are composed of a β-jellyroll-like periplasmic domain and six α-helical segments in the transmembrane domain. LptF and LptG form a central cavity containing highly conserved hydrophobic residues. Structural and functional studies suggest that LptBFG uses an alternating lateral access mechanism to extract lipopolysaccharide and traffic it along the hydrophobic cavity toward the transporter's periplasmic domains.Lipopolysaccharides (LPS) are synthesized at the periplasmic side of the inner membrane of Gram-negative bacteria and are then extracted by the LptBFG complex during the first step of LPS transport to the outer membrane. Here the authors present the LptBFG structure, which supports an alternating lateral access mechanism for LPS extraction.

PubMed: 28790314
DOI: 10.1038/s41467-017-00273-5

Experimental method

X-RAY DIFFRACTION (3.7 Å)