How Fungi Fight Fungi: The Science Behind Leucinostatins

Purpureocillium lilacinum PLBJ-1 is a biocontrol fungus. It makes leucinostatins. These are special molecules that can kill other fungi. Think of them as natural antibiotics. But how does this fungus make them? And why does it make more in some conditions than others? Scientists found out that the fungus makes more leucinostatins in a special homemade broth. This broth is called PDB-M. It's different from the store-bought kind, PDB-C. The big difference? The pH level and the amount of nitrogen. pH is a measure of how acidic or basic something is. Nitrogen is an important nutrient. The fungus likes it when the environment is more alkaline. That means it's less acidic. It also likes it when there's less nitrogen around. These conditions help it make more leucinostatins. But how does the fungus know how to adjust to these conditions? It uses two special proteins. These are PlPacC and PlAreB.PlPacC helps the fungus deal with changes in pH. PlAreB helps it manage nitrogen levels. Scientists used a tool called CRISPR-Cas9 to turn off these proteins. When they turned off PlPacC, the fungus couldn't control the pH well. It also made fewer leucinostatins. When they turned off PlAreB, the fungus made more leucinostatins. But it grew less and made fewer spores. This shows that both pH and nitrogen levels are important. They help the fungus make leucinostatins. The two proteins, PlPacC and PlAreB, play big roles in this process. Understanding this can help scientists make more leucinostatins. This could be useful for making natural antifungal treatments.