Format

Send to

Choose Destination
Mol Microbiol. 2017 Sep;105(6):839-859. doi: 10.1111/mmi.13740. Epub 2017 Jul 7.

Mapping the recognition domains of pneumococcal fibronectin-binding proteins PavA and PavB demonstrates a common pattern of molecular interactions with fibronectin type III repeats.

Author information

1
Department Genetics of Microorganisms, Interfaculty Institute for Genetics and Functional Genomics, University of Greifswald, Greifswald, D-17487, Germany.
2
Department of Structural Biology, Institute for Biochemistry, University of Greifswald, Greifswald, D-17487, Germany.
3
Department of Chemical Biology, Helmholtz Centre for Infection Research and German Centre for Infection Research (DZIF), Braunschweig, D-38124, Germany.
4
Central Facility for Microscopy, ZEIM, Helmholtz Centre for Infection Research, Braunschweig, D-38124, Germany.
5
Research Center for Infectious Diseases, University of Würzburg, Würzburg, D-97070, Germany.
6
Department of Oral and Dental Science, University of Bristol, Bristol, UK.

Abstract

Colonization of mucosal respiratory surfaces is a prerequisite for the human pathobiont Streptococcus pneumoniae (the pneumococcus) to cause severe invasive infections. The arsenal of pneumococcal adhesins interacts with a multitude of extracellular matrix proteins. A paradigm for pneumococci is their interaction with the adhesive glycoprotein fibronectin, which facilitates bacterial adherence to host cells. Here, we deciphered the molecular interaction between fibronectin and pneumococcal fibronectin-binding proteins (FnBPs) PavA and PavB respectively. We show in adherence and binding studies that the pneumococcal interaction with fibronectin is a non-human specific trait. PavA and PavB target at least 13 out of 15 type III fibronectin domains as demonstrated in ligand overlay assays, surface plasmon resonance studies and SPOT peptide arrays. Strikingly, both pneumococcal FnBPs recognize similar peptides in targeted type III repeats. Structural comparisons revealed that the targeted type III repeat epitopes cluster on the inner strands of both β-sheets forming the fibronectin domains. Importantly, synthetic peptides of FnIII1 , FnIII5 or FnIII15 bind directly to FnBPs PavA and PavB respectively. In conclusion, our study suggests a common pattern of molecular interactions between pneumococcal FnBPs and fibronectin. The specific epitopes recognized in this study can potentially be tested as antimicrobial targets in further scientific endeavours.

PMID:
28657670
DOI:
10.1111/mmi.13740
[Indexed for MEDLINE]
Free full text

Supplemental Content

Full text links

Icon for Wiley
Loading ...
Support Center