Cytochrome c oxidase is one of the key enzymes providing the ability to produce phenazines in Pseudomonas chlororaphis subsp. aurantiaca

Abstract

Phenazines are heteroaromatic compounds consist of a central pyrazine ring fused with two benzenes. Various functional groups linked to the dibenzopyrasine core cause differences in chemical, physical and biological properties of phenazines. The interest to these substances does not reduce in several decades. New biological activities and practical applications discovered in recent years force the researchers to study all aspects of phenazines synthesis, degradation and mechanisms of their action.In this study, we demonstrated the involvement of coxA gene product (cytochrome c oxidase, su I) in phenazines biosynthesis in P. chlororaphis subsp. aurantiaca. Overlap PCR was used to knockout coxAgene and derived mutants were analyzed for their ability to grow on rich and minimal culture media, as well as for the phenazines production level. We showed that the product of coxA gene is necessary for the phenazines production in rich growth media. At the same time CoxA protein seems has no effect on phenazines production in M9 minimal salts medium. CoxA protein is one of the core proteins of large transmembrane protein complex cytochrome c oxidase found in bacteria, archaea, and mitochondria of eukaryotes. We demonstrated that the knockout of even one subunit of this complex multiunit protein leads to a signi cant decrease (to trace concentrations) or complete suppression of phenazine antibiotics production on rich PCA-medium in P. chlororaphis subsp. aurantiaca.