Description_x000D_ Specificity_x000D_ The purified antibiotic has strong antifungal activity and is less efficient against bacteria or yeast._x000D_ Application_x000D_ Pyrrolnitrin from Pseudomonas cepacia has been used as a standard in the detection of pyrrolnitrin in Serratia marcescens cell culture extract._x000D_ Biochem/physiol Actions_x000D_ Pyrrolnitrin blocks the terminal electron transport between succinate or reduced NADH and coenzyme Q. In mitochondria preparations of S. cerevisiae, the antibiotic inhibited succinate oxidase, NADH oxidase, succinate cythochrome C reductase, and NADH-cytochrome C reductase. Pyrrolnitrin is involved in many cellular processes such as oxidative stress, electron transport, DNA and RNA synthesis._x000D_ Pyrrolnitrin is a metabolite, produced by Pseudomonas sp.