Download MendeleyStructure-Based Mechanism of Lipoteichoic Acid Synthesis by Staphylococcus Aureus Ltas.
Lu, D., Wormann, M.E., Zhang, X., Schneewind, O., Grundling, A., Freemont, P.S.(2009) Proc Natl Acad Sci U S A 106: 1584
- PubMed: 19168632
- DOI: https://doi.org/10.1073/pnas.0809020106
- Primary Citation of Related Structures:
2W5Q, 2W5R, 2W5S, 2W5T - PubMed Abstract:
Staphylococcus aureus synthesizes polyglycerol-phosphate lipoteichoic acid (LTA) from phosphatidylglycerol. LtaS, a predicted membrane protein with 5 N-terminal transmembrane helices followed by a large extracellular part (eLtaS), is required for staphylococcal growth and LTA synthesis. Here, we report the first crystal structure of the eLtaS domain at 1.2-A resolution and show that it assumes a sulfatase-like fold with an alpha/beta core and a C-terminal part composed of 4 anti-parallel beta-strands and a long alpha-helix. Overlaying eLtaS with sulfatase structures identified active site residues, which were confirmed by alanine substitution mutagenesis and in vivo enzyme function assays. The cocrystal structure with glycerol-phosphate and the coordination of a Mn(2+) cation allowed us to propose a reaction mechanism, whereby the active site threonine of LtaS functions as nucleophile for phosphatidylglycerol hydrolysis and formation of a covalent threonine-glycerolphosphate intermediate. These results will aid in the development of LtaS-specific inhibitors for S. aureus and many other Gram-positive pathogens.
Organizational Affiliation:
Division of Molecular Biosciences, Department of Microbiology, Imperial College London, South Kensington Campus, London SW7 2AZ, United Kingdom.
