Structure-function analysis of Heterodimer Formation, oligomerization, and receptor binding of the staphylococcus aureus bi-component toxin LukGH
(2015) In Journal of Biological Chemistry 290(1). p.142-156- Abstract
The bi-component leukocidins of Staphylococcus aureus are important virulence factors that lyse human phagocytic cells and contribute to immune evasion. The γ-hemolysins (HlgAB and HlgCB) and Panton-Valentine leukocidin (PVL or LukSF) were shown to assemble from soluble subunits into membrane-bound oligomers on the surface of target cells, creating barrel-like pore structures that lead to cell lysis. LukGH is the most distantly related member of this toxin family, sharing only 30-40% amino acid sequence identity with the others. We observed that, unlike other leukocidin subunits, recombinant LukH and LukG had low solubility and were unable to bind to target cells, unless both components were present. Using biolayer interferometry and... (More)
The bi-component leukocidins of Staphylococcus aureus are important virulence factors that lyse human phagocytic cells and contribute to immune evasion. The γ-hemolysins (HlgAB and HlgCB) and Panton-Valentine leukocidin (PVL or LukSF) were shown to assemble from soluble subunits into membrane-bound oligomers on the surface of target cells, creating barrel-like pore structures that lead to cell lysis. LukGH is the most distantly related member of this toxin family, sharing only 30-40% amino acid sequence identity with the others. We observed that, unlike other leukocidin subunits, recombinant LukH and LukG had low solubility and were unable to bind to target cells, unless both components were present. Using biolayer interferometry and intrinsic tryptophan fluorescence we detected binding of LukH to LukG in solution with an affinity in the low nanomolar range and dynamic light scattering measurements confirmed formation of a heterodimer. We elucidated the structure of LukGH by x-ray crystallography at 2.8-A˚ resolution. This revealed an octameric structure that strongly resembles that reported for HlgAB, but with important structural differences. Structure guided mutagenesis studies demonstrated that three salt bridges, not found in other bi-component leukocidins, are essential for dimer formation in solution and receptor binding. We detected weak binding of LukH, but not LukG, to the cellular receptor CD11b by biolayer interferometry, suggesting that in common with other members of this toxin family, the S-component has the primary contact role with the receptor. Thesenewinsights provide the basis for novel strategies to counteract this powerful toxin and Staphylococcus aureus pathogenesis.
(Less)
- author
- publishing date
- 2015-01-02
- type
- Contribution to journal
- publication status
- published
- subject
- in
- Journal of Biological Chemistry
- volume
- 290
- issue
- 1
- pages
- 15 pages
- publisher
- American Society for Biochemistry and Molecular Biology
- external identifiers
-
- pmid:25371205
- scopus:84920531939
- ISSN
- 0021-9258
- DOI
- 10.1074/jbc.M114.598110
- language
- English
- LU publication?
- no
- additional info
- Publisher Copyright: © 2015 by The American Society for Biochemistry and Molecular Biology, Inc.
- id
- 0c6050ea-fcd9-433f-9c6a-11697bb89d30
- date added to LUP
- 2022-04-25 11:23:27
- date last changed
- 2024-07-25 17:03:14
@article{0c6050ea-fcd9-433f-9c6a-11697bb89d30, abstract = {{<p>The bi-component leukocidins of Staphylococcus aureus are important virulence factors that lyse human phagocytic cells and contribute to immune evasion. The γ-hemolysins (HlgAB and HlgCB) and Panton-Valentine leukocidin (PVL or LukSF) were shown to assemble from soluble subunits into membrane-bound oligomers on the surface of target cells, creating barrel-like pore structures that lead to cell lysis. LukGH is the most distantly related member of this toxin family, sharing only 30-40% amino acid sequence identity with the others. We observed that, unlike other leukocidin subunits, recombinant LukH and LukG had low solubility and were unable to bind to target cells, unless both components were present. Using biolayer interferometry and intrinsic tryptophan fluorescence we detected binding of LukH to LukG in solution with an affinity in the low nanomolar range and dynamic light scattering measurements confirmed formation of a heterodimer. We elucidated the structure of LukGH by x-ray crystallography at 2.8-A˚ resolution. This revealed an octameric structure that strongly resembles that reported for HlgAB, but with important structural differences. Structure guided mutagenesis studies demonstrated that three salt bridges, not found in other bi-component leukocidins, are essential for dimer formation in solution and receptor binding. We detected weak binding of LukH, but not LukG, to the cellular receptor CD11b by biolayer interferometry, suggesting that in common with other members of this toxin family, the S-component has the primary contact role with the receptor. Thesenewinsights provide the basis for novel strategies to counteract this powerful toxin and Staphylococcus aureus pathogenesis.</p>}}, author = {{Badarau, Adriana and Rouha, Harald and Malafa, Stefan and Logan, Derek T. and Håkansson, Maria and Stulik, Lukas and Dolezilkova, Ivana and Teubenbacher, Astrid and Gross, Karin and Maierhofer, Barbara and Weber, Susanne and Jägerhofer, Michaela and Hoffman, David and Nagy, Eszter}}, issn = {{0021-9258}}, language = {{eng}}, month = {{01}}, number = {{1}}, pages = {{142--156}}, publisher = {{American Society for Biochemistry and Molecular Biology}}, series = {{Journal of Biological Chemistry}}, title = {{Structure-function analysis of Heterodimer Formation, oligomerization, and receptor binding of the <i>staphylococcus aureus</i> bi-component toxin LukGH}}, url = {{http://dx.doi.org/10.1074/jbc.M114.598110}}, doi = {{10.1074/jbc.M114.598110}}, volume = {{290}}, year = {{2015}}, }