Defining the domain organization of K1-like killer toxins

Conserved alpha domains in K1-like killer toxins across yeast species are linked to cytotoxicity, regardless of antifungal activity in full-length toxins.

• Why it matters: Understanding the domain organization and processing of yeast killer toxins is crucial for insights into their evolution and functional diversity, which may impact antifungal strategies.
• What they did: The study identified domain boundaries in K1 homologs through primary sequence analysis and proteolytic processing sites, and tested their function with assays on toxin activity and toxicity.
• The result: Many K1 homologs contain cytotoxic alpha domains, and some toxins lacking antifungal activity still exhibit toxicity via alpha domains alone, highlighting conserved toxicity mechanisms.