摘要

Two Pseudomonas aurantiaca mutant strains overproducing phenazine antibiotics (synthesis levels of 210 and 410 mg/l, respectively) along with wild-type bacteria (production level of 71-75 mg/l) and a phzmutant not producing phenazines were used to study the changes in the activity of the antioxidant complex components, that is, catalase, superoxide dismutase (SOD), glutathione reductase, and NADH oxidase; glutathione concentration (in both reduced and oxidized forms); and activity of acyl-CoA synthetase, the key enzyme of cell metabolism.
Bacterial producers were found to respond to an increase in intra- and extracellular phenazines by induction of catalase, SOD, glutathione reductase, and glutathione synthesis. However, while in the case of catalase and glutathione reductase this trend was observed in all the strains under study, the activity of SOD at a high level of phenazine synthesis (in particular, 410 mg/l) decreased somewhat, probably due to high its sensitivity to high concentrations of H(2)O(2) generated by phenazines. Decrease in SOD activity was compensated by increase in the synthesis rates of glutathione and glutathione reductase. NADH oxidase was shown to be practically uninvolved in formation of P. aurantiaca response toward phenazine accumulation, and acyl-CoA synthetase activity was found to decrease.

  • 出版日期2010-8