Production of catalases by Comamonas spp. and resistance to oxidative stress.
Bacterial isolates Comamonas terrigena N3H (from soil contaminated with crude oil) and C. testosteroni (isolated from the sludge of a wastewater treatment plant), exhibit much higher total catalase activity than the same species from laboratory collection cultures. Electrophoretic resolution of catalases revealed only one corresponding band in cell-free extracts of both C. testosteroni cultures. Isolates of C. terrigena N3H exhibited catalase-1 and catalase-2 activity, whereas in the collection culture C. terrigena ATCC 8461 only catalase-1 was detected. The environmental isolates exhibited much higher resistance to exogenous H2O2 (20, 40 mmol/L) than collection cultures, mainly in the middle and late exponential growth phases. The stepwise H2O2-adapted culture of C. terrigena N3H, which was more resistant to oxidative stress than the original isolate, exhibited an increase of catalase and peroxidase activity represented by catalase-1. Pretreatment of cells with 0.5 mmol/L H2O2 followed by an application of the oxidative agent in toxic concentrations (up to 40 mmol/L) increased the rate of cell survival in the original isolate, but not in the H2O2-adapted variant. The protection of bacteria caused by such pretreatment corresponded with stimulation of catalase activity in pretreated culture.
Godocíková
J
J
Institute of Molecular Biology, Centre of Excellence, Slovak Academy of Sciences, 845 51 Bratislava, Slovakia. Jana.Godocikova@savba.sk
Bohácová
V
V
Zámocký
M
M
Polek
B
B
D002374:Catalase / Q000096:biosynthesis*; D020585:Comamonas / Q000187:drug effects / Q000201:enzymology / Q000254:growth & development* / Q000302:isolation & purification; D024881:Drug Resistance, Bacterial; D006861:Hydrogen Peroxide / Q000494:pharmacology*; D018384:Oxidative Stress / Q000502:physiology*; D010578:Petroleum; D012722:Sewage / Q000382:microbiology; D012988:Soil Microbiology; D012989:Soil Pollutants; D014865:Waste Disposal, Fluid
D010578:Petroleum; D012722:Sewage; D012989:Soil Pollutants; D006861:Hydrogen Peroxide; D002374:Catalase