PDBsum entry 4p33

Hydrolase

PDB id: 4p33

Contents

Protein chains

235 a.a.

Ligands

ATP ×2

GOL ×5

Metals

_NA ×2

Waters ×149

PDB id:

4p33

Name:

Hydrolase

Title:

Crystal structure of e. Coli lptb-e163q in complex with atp-sodium

Structure:

Lipopolysaccharide export system atp-binding protein lptb. Chain: a, b. Engineered: yes. Mutation: yes

Source:

Escherichia coli. Organism_taxid: 83333. Strain: k12. Gene: lptb, yhbg, b3201, jw3168. Expressed in: escherichia coli. Expression_system_taxid: 1452720.

Resolution:

1.65Å R-factor: 0.189 R-free: 0.210

Authors:

D.J.Sherman,M.B.Lazarus,L.Murphy,C.Liu,S.Walker,N.Ruiz,D.Kahne

Key ref:

D.J.Sherman et al. (2014). Decoupling catalytic activity from biological function of the ATPase that powers lipopolysaccharide transport. Proc Natl Acad Sci U S A, 111, 4982-4987. PubMed id: 24639492 DOI: 10.1073/pnas.1323516111

Date:

07-Feb-14 Release date: 26-Mar-14

Protein chains

P0A9V1  (LPTB_ECOLI) -  Lipopolysaccharide export system ATP-binding protein LptB from Escherichia coli (strain K12)

Seq: 241 a.a.

Struc: 235 a.a.*

* PDB and UniProt seqs differ at 1 residue position (black cross)

Enzyme reactions

• Enzyme class: E.C.7.5.2.- - ?????

DOI no: 10.1073/pnas.1323516111

Proc Natl Acad Sci U S A 111:4982-4987 (2014)

PubMed id: 24639492

Decoupling catalytic activity from biological function of the ATPase that powers lipopolysaccharide transport.

D.J.Sherman, M.B.Lazarus, L.Murphy, C.Liu, S.Walker, N.Ruiz, D.Kahne.

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.