Core structure of the outer membrane lipoprotein from Escherichia coli at 1.9 A resolution.Shu, W., Liu, J., Ji, H., Lu, M.
(2000) J Mol Biol 299: 1101-1112
- PubMed: 10843861
- DOI: https://doi.org/10.1006/jmbi.2000.3776
- Primary Citation of Related Structures:
- PubMed Abstract:
The outer membrane lipoprotein of the Escherichia coli cell envelope has characteristic lipid modifications at an amino-terminal cysteine and can exist in a form bound covalently to the peptidoglycan through a carboxyl-terminal lysine. The 56-residue polypeptide moiety of the lipoprotein, designated Lpp-56, folds into a stable, trimeric helical structure in aqueous solution. The 1.9 A resolution crystal structure of Lpp-56 comprises a parallel three-stranded coiled coil including a novel alanine-zipper unit and two helix-capping motifs. The amino-terminal motif forms a hydrogen-bonding network anchoring an umbrella-shaped fold. The carboxyl-terminal motif uses puckering of the tyrosine side-chains as a unique docking arrangement in helix termination. The structure provides an explanation for assembly and insertion of the lipoprotein molecules into the outer membrane of gram-negative bacteria and suggests a molecular target for antibacterial drug discovery.
Department of Biochemistry, Weill Medical College of Cornell University, New York, NY, 10021, USA.