Receptor Binding Domains of TcdB from Clostridioides difficile for Chondroitin Sulfate Proteoglycan-4 and Frizzled Proteins Are Functionally Independent and Additive
Open Access
- 23 November 2020
- Vol. 12 (12), 736
- https://doi.org/10.3390/toxins12120736
Abstract
Toxin B (TcdB) produced by Clostridioides difficile is a main pathogenicity factor that affects a variety of different cell types within the colonic mucosa. TcdB is known to utilize frizzled-1,2,7 and chondroitin sulfate proteoglycan-4 (CSPG4) as protein receptors. By using human cervical cancer cell line HeLa CSPG4 knockout (CSPG4−/−) cells as well as TcdB mutants which do not bind to either CSPG4 or frizzled-1,2,7, or both, we evaluated the impact of the individual receptors for cytopathic and cytotoxic effects of TcdB. We compared TcdB from the reference strain VPI10463 (TcdBVPI) and the endemic strain R20291 (TcdBR20) which does not interact with frizzled-1,2,7. TcdBVPI devoid of CSPG4 binding (TcdBVPI ΔCROP) shows identical cytopathic potency as full-length TcdB in HeLa CSPG4−/− cells, indicating that interaction with frizzled proteins is not affected in the presence of the C-terminal CROP domain. We validated CSPG4 as cellular receptor for both TcdB toxinotypes in HeLa and HEp-2 cells. By exchange of a single phenylalanine residue, 1597 with serine, we generated a mutated TcdBVPI variant (TcdBVPI F1597S) that in accordance with TcdBR20 lacks binding to frizzled-1,2,7 and showed identical potency as TcdBR20 on HeLa cells. This enabled us to estimate the respective share of CSPG4 and frizzled-1,2,7 in the cytotoxic and cytopathic effect induced by TcdB. Our data reveal that binding to frizzled-1,2,7 and to CSPG4 occurs independently and in an additive manner.This publication has 38 references indexed in Scilit:
- LRP1 is a receptor for Clostridium perfringens TpeL toxin indicating a two-receptor model of clostridial glycosylating toxinsProceedings of the National Academy of Sciences of the United States of America, 2014
- Clostridium difficile toxin B-induced necrosis is mediated by the host epithelial cell NADPH oxidase complexProceedings of the National Academy of Sciences of the United States of America, 2013
- NG2/CSPG4-collagen type VI interplays putatively involved in the microenvironmental control of tumour engraftment and local expansionJournal of Molecular Cell Biology, 2013
- The Repetitive Oligopeptide Sequences Modulate Cytopathic Potency but Are Not Crucial for Cellular Uptake of Clostridium difficile Toxin APLOS ONE, 2011
- NG2 expression predicts the metastasis formation in soft‐tissue sarcoma patientsJournal of Orthopaedic Research, 2008
- Involvement of the nectin-afadin complex in PDGF-induced cell survivalJournal of Cell Science, 2008
- Crystal structure of receptor-binding C-terminal repeats from Clostridium difficile toxin AProceedings of the National Academy of Sciences of the United States of America, 2005
- Clostridium difficileToxins: Mechanism of Action and Role in DiseaseClinical Microbiology Reviews, 2005
- Molecular cloning of a human melanoma-associated chondroitin sulfate proteoglycan.Proceedings of the National Academy of Sciences of the United States of America, 1996
- Interaction of the NG2 chondroitin sulfate proteoglycan with type VI collagen.The Journal of cell biology, 1990