Increase of Phenazine Antibiotic Production in Bacteria Pseudomonas Aurantiaca by Cloning the Cluster of phzIR-Genes (pp. 195-206)
Authors: (E.G. Veremeenko, N.P. Maksimova, Belarusian State University, Minsk, Belarus)
Abstract: The gene-engineering strains capable to produce phenazine antibiotics were derived from wild type bacteria P. aurantiaca and mutant cultures obtained earlier (strain B-162/255). We carried out cloning of phzIR-genes encoding positive regulators of phenazine antibiotic synthesis in P. aurantiaca. The greatest positive effect of recombinant construction was recorded in wild type bacteria B-162 – production level increased 5.4 times and was 410 mg/l. At the same time mutant strain B-162/255, distinguished by enhanced productivity (420 mg/l) showed only 1.2 times rise to 500 mg/l in presence of additional copies of phzIR-genes. The antioxidant status of recombinant cells was examined. It was shown, that use of antioxidants as the additives into cultural medium gives some chance to overcome the negative effect of high concentrations of native phenazines on cells-producers and additionally increase phenazine yield to 842 mg/l.