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

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 α-hemolysin stands out for being the most thoroughly studied variant. In this work, we show the production and purification of S. aureus α-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.