Natural Products in Microbial Interactions

The search for new bioactive natural products has prompted scientists to exploit environmental niches in which the production of these compounds is ecologically motivated. Microbial predator–prey interactions are particularly rich sources of natural products. We describe one such interaction in which bacterivorous amoebae and their prokaryotic prey meet. Amoebae are voracious and ubiquitous predators to bacteria that cause constant depletion of huge bacterial reservoirs. This puts both organisms under strong evolutionary selection pressure: the bacteria have evolved mechanisms to prevent grazing and the amoebae must counteract or surmount these mechanisms in order to survive. Here, we describe a variety of natural products that show amoebicidal activity, along with investigations into their biosynthesis, evolution, and regulation.