Antioxidant enzymes and reactive oxygen species level of the Achromobacter xylosoxidans bacteria during hydrocarbons biotransformation

Abstract

The level of catalase and superoxide dismutase induction, as well as generation of superoxide anion radical in cells and accumulation of hydrogen peroxide in the culture medium were researched in three strains of oil-degrading bacteria Achromobacter xylosoxidans at cultivation in rich nutrient medium and in the media with hydrocarbons as the only source of carbon. The effects of pentane, decane, hexadecane, cyclohexane, benzene, naphthalene and diesel fuel were evaluated. It was determined that in the microbial cell on media with hydrocarbons, the generation of superoxide anion radical increases, accumulation of hydrogen peroxide and induction of superoxide dismutase synthesis occur, and catalase activity is reduced. Oxidative stress in the cells of A. xylosoxidans was caused by biotransformation of all the studied hydrocarbons. The most pronounced effect was observed at incubation of bacteria with cyclohexane, pentane, diesel fuel, benzene and naphthalene.

Cyclohexane, naphthalene, and diesel fuel increase oxidative stress, CYP153, sodA, and recA gene expression in Rhodococcus erythropolis

“…The present data obtained for R. erythropolis coincided with our previous results of reactive oxygen species production by Acinetobacter calcoaceticus (Sazykin et al, ) and Achromobacter xylosoxidans (Sazykin et al, ). Namely, O 2 ·− production increased during first 12 hr of bacteria incubation with hydrocarbons, and then it decreased.…”

“…However, microorganisms of different bacterial taxa differ in ROS generation depending on hydrocarbons type. In R. erythropolis and A. xylosoxidans (Sazykin et al, ), the maximum production of O 2 ·− was caused by cyclohexane, and in A. calcoaceticus —by diesel fuel and PAHs (Sazykin et al, ). Most likely, it is associated with great importance of O 2 ·− production in a prokaryotic cell when shunting an enzymatic cycle by suboptimum substrates, and, respectively, presence of hydrocarbons oxidases with different specificities in various microorganisms.…”

“…Hydrocarbons have a similar effect on A. calcoaceticus and A. xylosoxidans . Besides, reduction of catalase activity has been registered in such microorganisms as Gordona terrae, Rhodococcus rubropertinctus, R. erythropolis, A. calcoaceticus, and A. xylosoxidans in the course of hydrocarbons biotransformation (Gogoleva, Nemtseva, & Bukharin, ; Sazykin et al, , ). The reduction of catalase activity promotes H 2 O 2 accumulation and organic substrates oxidation by ROS in cells environment.…”

“…Luminescence level in a well was determined within 100 s after addition of peroxidase with an interval of 1 s. For each measurement, the average value of CL intensity was calculated and subsequently, the biggest average CL value was used (Sazykin et al, , ). Three independent experiments were carried out 8 times.…”

“…Bacteria cultivated in Luria-Bertani (LB) and basic mineral salt medium described before (Sazykin et al, 2016). Fifty-microliter Erlenmeyer flasks containing 20 ml of medium were cultivated at 170 rpm and 30°C in an orbital shaker incubator Innova 40R (New Brunswick, USA).…”