Beschreibung:
<jats:title>Abstract</jats:title><jats:p>Bacterial defense mechanisms have evolved to protect bacteria against predation by nematodes, predatory bacteria, or amoebae. We identified novel bacterial alkaloids (pyreudiones A–D) that protect the producer, <jats:italic>Pseudomonas fluorescens</jats:italic> HKI0770, against amoebal predation. Isolation, structure elucidation, total synthesis, and a proposed biosynthetic pathway for these structures are presented. The generation of <jats:italic>P. fluorescens</jats:italic> gene‐deletion mutants unable to produce pyreudiones rendered the bacterium edible to a variety of soil‐dwelling amoebae.</jats:p>