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bioRxiv · 10.1101/2023.07.19.549664

A streamlined method to obtain biologically active TcdA and TcdB toxins from Clostridioides difficile

Sapa, A. A. D.·Brosse, A.·Coullon, H.·Pean de Ponfilly, G.·Candela, T.·Le Monnier, A.
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Abstract

The major virulence factors of Clostridioides difficile (C. difficile) are enterotoxin A (TcdA) and cytotoxin B (TcdB). The study of toxins is a crucial step in exploring the virulence of this pathogen. Currently, the toxin purification process is either laborious and time-consuming in C. difficile or performed in heterologous hosts. Therefore, we propose a streamlined method to obtain functional toxins in C. difficile. Two C. difficile strains were generated each harboring a sequence encoding a His-tag at the 3 end of C. difficile 630{Delta}erm tcdA or tcdB genes. Each toxin gene is expressed using the Ptet promoter inducible by anhydro-tetracycline. The purification yields were estimated to be 0.28 mg per liter and 0.1 mg per liter for rTcdA and rTcdB, respectively. In this study, we successfully developed a simple routine method that allows the production and purification of biologically rTcdA and rTcdB active toxins with similar activities compared to native toxins.

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Sapa, A. A. D., Brosse, A., Coullon, H., Pean de Ponfilly, G., Candela, T., Le Monnier, A.. 2023-07-19. A streamlined method to obtain biologically active TcdA and TcdB toxins from Clostridioides difficile. https://doi.org/10.1101/2023.07.19.549664

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