The anatomical and ultrastructural features of the leaf and their changes under stress conditions are considered in relation to the adaptations of D. antarctica to the climate conditions in the Maritime Antarctic.

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The regulation of lipoxygenases (LOX) activity was studied in Arabidopsis thaliana grown under excess Cd and Cu (0.0, 5.0, 50.0 lM) in solution cultures for 7 days. The LOX activity was determined spectrophotometrically at 234 nm in the leaves of mature plants using linoleic and linolenic acids as substrates, while their cellular localization was assessed by immunogold-labelling. The LOX mainly occurred in the cytoplasm as well as inside the chloroplasts. Two bands of LOX were found in the leaves of A. thaliana, but one more band appeared in plants treated with 50.0 lM Cu. Despite the lower amount of enzymatic protein in plants exposed to heavy metals, the enzyme activity was significantly higher than that in the control; it was especially high at pH 8.0 when linolenic acid was used as a substrate. The role of the redox state of plant cells in modifying the LOX activity was also discussed. The changes in ultra-structure of the leaf parenchyma cells were more evident in A. thaliana plants treated with Cd than those treated with Cu.

Aims: The aim of our research was to isolate the compounds from the metabolites of Raoultella ornithinolytica with the activity against Candida albicans and to analyse the action of the compounds on the metabolic activity and morphology of the fungus cells. Methods and Results: The effect of active protein fractions on the cell morphology, growth, and metabolic activity of C. albicans was analysed under a light microscope with Nomarski contrast and after staining with calcofluorwhite. The LIVE/DEAD Yeast Viability Kit F-7030 FUN 1 was used for determination of C. albicans metabolic activity. The biomolecules obtained after isolation by ion exchange chromatography were further fractionated by Sephadex G-50 medium gel filtration. Then, after molecular sieve, the fractions were analysed by FTIR and SERS Spectroscopy. A subfraction was isolated from the antifungal protein fraction above 100 kDa. The active subfraction identified as the glyco-protein complex caused a decrease in the metabolic activity and morphological changes of C. albicans cells. Conclusions: The glyco-protein complex obtained from metabolites of bacteria Raoultella ornithinolytica possesses antifungal activity against C. albicans and shows minimal toxicity (1%) against fibroblasts. Significance and Impact of the Study: Studies on the glyco-protein complex obtained from earthworm gut bacteria R. ornithinolytica can lead to their application in biological fungicide and pharmaceutical industry.

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