Recombinant production in Escherichia coli of functionally active alpha-hemolysin from the human pathogen Staphylococcus aureus

Diaz-Varela, J. L.; Sabia, V.; Heras-Marquez, D.; Laxalde-Fernandez, D.; Martinez-del-Pozo, A.; Garcia-Linares, S.

doi:10.1101/2025.01.14.632992

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bioRxiv · 10.1101/2025.01.14.632992

Recombinant production in Escherichia coli of functionally active alpha-hemolysin from the human pathogen Staphylococcus aureus

Diaz-Varela, J. L.·Sabia, V.·Heras-Marquez, D.·Laxalde-Fernandez, D.·Martinez-del-Pozo, A.·Garcia-Linares, S.

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Abstract

Staphylococcus aureus is a human opportunistic pathogen capable of causing multiple infections in both humans and animals. It secretes a group of exotoxins, known as hemolysins, which are released to enhance its pathogenicity. All of them exhibit cytolytic activity on a variety of host cell types, but -hemolysin stands out for being the most thoroughly studied variant. In this work, we show the production and purification of S. aureus -hemolysin following a straightforward protocol and in sufficient quantity to consider it as a potential procedure for future biotechnological approaches. Functional and structural characterization has indeed revealed that the protein is fully functional, confirming the key role of cholesterol in the necessary protein-lipid interaction. Furthermore, it has also been shown that the purified toxin can be assembled into single-particle individual pores within soluble lipid platforms in the form of cholesterol-containing nanodiscs.

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Diaz-Varela, J. L., Sabia, V., Heras-Marquez, D., Laxalde-Fernandez, D., Martinez-del-Pozo, A., Garcia-Linares, S.. 2025-01-15. Recombinant production in Escherichia coli of functionally active alpha-hemolysin from the human pathogen Staphylococcus aureus. https://doi.org/10.1101/2025.01.14.632992

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