4P32

Crystal structure of E. coli LptB in complex with ADP-magnesium

Summary for 4P32

• Entry DOI: 10.2210/pdb4p32/pdb
• Related: 4P31 4P33
• Descriptor: Lipopolysaccharide export system ATP-binding protein LptB, ADENOSINE-5'-DIPHOSPHATE, MAGNESIUM ION, ... (4 entities in total)
• Functional Keywords: abc transporter, nucleotide-binding domain, atpase, atp binding, hydrolase
• Biological source: Escherichia coli
• Total number of polymer chains: 2
• Total formula weight: 56784.53

Authors

Sherman, D.J.,Lazarus, M.B.,Murphy, L.,Liu, C.,Walker, S.,Ruiz, N.,Kahne, D. (deposition date: 2014-03-05, release date: 2014-03-26, Last modification date: 2023-09-27)

Primary citation

Sherman, D.J.,Lazarus, M.B.,Murphy, L.,Liu, C.,Walker, S.,Ruiz, N.,Kahne, D.
Decoupling catalytic activity from biological function of the ATPase that powers lipopolysaccharide transport.
Proc.Natl.Acad.Sci.USA, 111:4982-4987, 2014

PubMed Abstract: The cell surface of Gram-negative bacteria contains lipopolysaccharides (LPS), which provide a barrier against the entry of many antibiotics. LPS assembly involves a multiprotein LPS transport (Lpt) complex that spans from the cytoplasm to the outer membrane. In this complex, an unusual ATP-binding cassette transporter is thought to power the extraction of LPS from the outer leaflet of the cytoplasmic membrane and its transport across the cell envelope. We introduce changes into the nucleotide-binding domain, LptB, that inactivate transporter function in vivo. We characterize these residues using biochemical experiments combined with high-resolution crystal structures of LptB pre- and post-ATP hydrolysis and suggest a role for an active site residue in phosphate exit. We also identify a conserved residue that is not required for ATPase activity but is essential for interaction with the transmembrane components. Our studies establish the essentiality of ATP hydrolysis by LptB to power LPS transport in cells and suggest strategies to inhibit transporter function away from the LptB active site.

PubMed: 24639492
DOI: 10.1073/pnas.1323516111

Experimental method

X-RAY DIFFRACTION (1.55 Å)