5AZB: Crystal Structure Of Escherichia Coli Lgt In Complex With Phosphatidylglycerol And The Inhibitor Palmitic Acid

Lipoprotein biogenesis is essential for bacterial survival. Phosphatidylglycerol:prolipoprotein diacylglyceryl transferase (Lgt) is an integral membrane enzyme that catalyses the first reaction of the three-step post-translational lipid modification. Deletion of the lgt gene is lethal to most Gram-negative bacteria. Here we present the crystal structures of Escherichia coli Lgt in complex with phosphatidylglycerol and the inhibitor palmitic acid at 1.9 and 1.6 A resolution, respectively. The structures reveal the presence of two binding sites and support the previously reported structure-function relationships of Lgt. Complementation results of lgt-knockout cells with different mutant Lgt variants revealed critical residues, including Arg143 and Arg239, that are essential for diacylglyceryl transfer. Using a GFP-based in vitro assay, we correlated the activities of Lgt with structural observations. Together, the structural and biochemical data support a mechanism whereby substrate and product, lipid-modified lipobox-containing peptide, enter and leave the enzyme laterally relative to the lipid bilayer.
PDB ID: 5AZBDownload
MMDB ID: 135999
PDB Deposition Date: 2015/9/30
Updated in MMDB: 2016/02
Experimental Method:
x-ray diffraction
Resolution: 1.6  Å
Source Organism:
Similar Structures:
Biological Unit for 5AZB: monomeric; determined by author and by software (PISA)
Molecular Components in 5AZB
Label Count Molecule
Protein (1 molecule)
Prolipoprotein Diacylglyceryl Transferase(Gene symbol: lgt)
Molecule annotation
Chemicals (12 molecules)
* Click molecule labels to explore molecular sequence information.

Citing MMDB