Tag Archives: adaptation

Biochemical indicators of green photosynthetic bacteria Chlorobium limicola response to Cu(2+) action

T. B. Sehin1, S. O. Hnatush1, O. D. Maslovska1,
A. A. Halushka1, Y. H. Zaritska2

1Ivan Franko National University of Lviv, Ukraine;
2State Scientific-Research Control Institute of Veterinary
Medicinal Products and Feed Additives, Lviv, Ukraine;
e-mail: SeginT@ukr.net

Received: 11 March 2019; Accepted: 29 November 2019

Photolithotrophic sulfur bacteria are involved in  biota functioning and have  a biotechnological potential for bioremediation of contaminated environment, but the mechanisms of xenobiotics, in particular of heavy metal ions damaging action and the pathways of photolithotrophic bacteria adaptation  under these conditions have not been established. In this work, the biochemical indicators of green photosynthetic bacteria Chlorobium limicola response to Cu ions were studied. C. limicola cells were incubated during one hour in buffer containing copper (II) sulfate in 0.05–0.5 mM concentrations and grown for 8 days in GSB medium. The content of Cu2+ in cells was estimated by atomic absorption spectroscopy. The activity of enzymes of antioxidant defense, photosynthetic pigments and glutathione content, indexes of lipids unsaturation and membrane viscosity as markers of  membrane fluidity were estimated. It was shown that the response of green photosynthetic bacteria C. limicola to Cu2+ action varied  depending on cations concentration. Under the influence of metal salt at 0.05 mM concentration, the activity of antioxidant enzymes, GSH/GSSG ratio, the content of photosynthetic pigments and membrane fluidity indexes were higher as compared with control. Under the increase of copper (II) sulfate concentration to 0.25 mM, the activity of antioxidant  enzymes was lower compared to the response of the cells under the influence of 0.05 mM copper (II) and the GSSG content was increased.  Under the influence of 0.5 mM copper (II) the indexes of membrane fluidity did not differ from the control, but superoxide dismutase and peroxidase activity inhibition and  the further decrease of GSH/GSSG ratio were observed followed by the highest Cu2+ cations accumulation in cells and significant decrease of  bacteria biomass growth.

Carbohydrate and nitrogenous metabolism condition in the rat tissue under experimental rhabdomyolysis

P. A. Kaliman, S. M. Okhrimenko

Karazin Kharkiv National University, Ukraine;
e-mail: s.okhrimenko@mail.ru

Some effects of glycerol injection on indices of the condition of the thiol-disulfide system as well as carbohydrate and nitrogen metabolism in rats in vivo were studied. A decrease was revealed in levels of non-protein SH-groups in the liver, kidney and heart, as well as of protein SH-groups in the kidney and heart of rats following glycerol injection. That might be connected with SH-group oxidation under the excessive arrival of free haem into tissues under rhabdomyolysis. A decrease in glycogen and  increase in tyrosine aminotransferase activity in the liver were observed. Activation of nitrogenous metabolism following glycerol injection is indicated by the increase of aminotransferase activity in organs, and concentration of blood urea. High concentration of creatinine in the rat serum can reflect malfiltration in kidneys.

Lipoxygenases and plant cell metabolism regulation

I. V. Pokotylo, Y. S. Kolesnikov, M. V. Derevyanchuk, A. I. Kharitonenko, V. S. Kravets

Institute of Bioorganic Chemistry and Petrochemistry,
National Academy of Sciences of Ukraine, Kyiv;
e-mail: kravets@bpci.kiev.ua

Lipoxygenases are widespread plant enzymes that catalyze the peroxidation of polyunsaturated fatty acids. This reaction is pivotal in the enzymatic cascade that leads to production of numerous metabolism regulators named oxylipins. The activity of these biologically active substances is directly associated with defence reactions in conditions of biotic and abiotic stresses as well as with the regulation of plant growth, propagation and senescence. In this review the contemporary notions about lipoxygenases­ classification, structure and catalytic properties are summarized. The features of enzyme activity regulation by transcriptional and posttranslational mechanisms in addition to the role of lipoxygenase catalysis in plant cell signalling are discussed.