Vol 17, No 2 (2019)

Background. Linseed solin varieties were created for nutrition, but the effect of oil fatty acid (FA) composition on other characters is not clear.

Materials and methods. Using 6 inbreeding generations from 26 heterogeneous flax accessions were generated 19 high (HL), 7 medium (ML) and 14 low linolenic (LL) lines. For each lines contents of 5 basic FA: palmitic, stearic, oleic (OLE), linoleic (LIO) and linolenic (LIN); the ratio LIO/LIN, oil iodine number, vegetative period (VP) phases and plants size were evaluated. Development of CAPS marker for LuFAD3A gene was performed using idtdna.com. Sequencing of LIN genes sites was done in the Centre MCT SPBGU and Eurogen.

Results. ANOVA showed significant differences HL, ML and LL groups for PAL, OLE, LIO, LIN, LIO/LIN, IOD. Considerable decrease of LIN, causes asymmetric changes in FA ratio and correlations between them and other traits. Factor analysis revealed the influence of two factors. The first one divided lines according to their LIN level and characters associated with it, the second one – according to the VP and OLE. LIN synthesis is controlled by two complementary genes LuFAD3A and LuFAD3B. Sequencing of LuFAD3A gene 1 exon of 6 lines revealed a mutation (G₂₅₅ → A₂₅₅), resulting in formation of stop codon. Developed developed CAPS-marker confirmed the homozygosity of hybrids between LL (gc-391) and HL lines (gc-65, 109, 121). Descendants of hybrid between gc-109 and gc-391 ripened 8-10 days earlier than gc-391. CAPS markers of LuFAD3B gene revealed differences between HL, ML, LL lines. Sequencing of this gene first exon and the beginning of the second one in 3 lines (1HL, 2LL) showed that this method reveals a mutation in the second restriction site, located in the 2 exon (C₆ → T₆), and causing the replacement Hys → Tyr.

Conclusion. Lines from GC have wide variability of FA and other agronomic characters, combination of which will expand the cultivation of solin.

Background. Rhizobia are the most effective nitrogen-fixing organisms that can fix nitrogen only in symbiosis with leguminous plants. The general transcriptional activator of nitrogen fixation genes in diazotrophic bacteria is NifA. In this work, the possibility of modifying the regulation of nitrogen fixation in the nodule bacteria Mesorhizobium, Ensifer and Rhizobium was studied by introducing an additional copy of the nifA gene into the bacterial genomes during the regulation of induced bacterial promoters.

Materials and methods. A series of expression genetic constructs with NifA genes of nodule bacteria strains under the control of an inducible promoter Pm were created. The resulting constructs were transformed into strains of nodule bacteria. The obtained recombinant strains were investigated for the appearance of their nitrogen-fixing activity in the free-living state.

Results. It was shown that the expression of nifA in recombinant cells of all three genera of bacteria leads to the appearance of insignificant nitrogenase activity. At the same time, the level of nitrogenase activity does not have a correlation with the level of expression of the introduced nifA gene, which, most likely, is a consequence of the multilevel regulation of nitrogen fixation.

Conclusion. The possibility of artificial activation of nitrogenase activity in nodule bacteria in the free-living state by introducing the NifA regulatory protein gene into bacteria was shown.

Background. Experimental conditions allow to determine the structural and functional changes of polytene chromosomes under the influence of free ions of an individual metal.

Materials and methods. C. plumosus (L.) and G. glaucus (Mg) larvae were placed in solutions of lead nitrate: 0.01, 0.02, 0.1 and 0.5 mg/l. Exposure — 12 h. Analysis of preparations of polytene chromosomes was carried out using the Carl Zeiss PrimoStar microscope. The functional activity factor of the nucleolus organizer (NOR), the coefficient of genetic activity of the Balbiani ring (BRR) was calculated.

Results. Equations of the dependence of the change in the coefficients: NOR = 5,187–0,01 lnC for C. plumosus and NOR = 2,11–0,03 lnC for G. glaucus; BRR = 1,504–0,04 lnC for C. plumosus and BRR = 2,018 + 0,03 lnC for G. glaucus.

Conclusion. With an increase in the concentration of lead in both C. plumosus and G. glaucus decreases NOR, which implies a decrease in the intensity of protein biosynthesis processes. BRR decreases in C. plumosus and increases in G. glaucus. The different genome reactions of the two species indicate the existence of different mechanisms of adaptation to lead ions

Background. Natural aquatic ecosystems are the habitat of many organisms, a source of drinking water, a resource for human activities and are subjected to anthropogenic pressure. In this regard, interest in studying the genotoxicity and mutagenicity of surface waters has increased significantly. The aim of this study is to investigate the cytotoxic, genotoxic and mutagenic effects of the surface waters of the suburban area of Almaty.

Material and methods. The research materials were water samples of the rivers Esik, Turgen and Lake Esik. The atomic absorption method, lux-test, cytogenetic tests (Hordeum vulgare L.), phytotoxicity test (Allium cepa L.) and embryotoxicity (Danio rerio H.) were used.

Results. Physico-chemical water analysis revealed an excess of MPC for Mn, Pb, Cd, Zn. Using the lux-test on E. coli KatG strains, the pro-oxidant activity of Esik R. water. On the plant test objects revealed toxicity and mutagenicity of water samples. The results of bio-testing of natural waters with D. rerio revealed their high toxicity and teratogenicity for embryos at all stages of development.

Conclusion. The results of this study obtained on various test-systems and test-objects indicate that surface waters are contaminated by environmentally dangerous factors that pose a threat to biota and human health.

Teucrium polium (T. polium) and Rumex crispus (R. crispus) are plant species that grow widely in Anatolia and are thought to have healing effects for many diseases. In this study plant extracts are suggested as alternative agents in repairing cellular damage by using sister chromatid exchange (SCE), micronucleus (MN), mitotic index (MI), replication index (RI) and nuclear abnormalities (NAs), against the genotoxicity of cyclophosphamide (CP) in the human lymphocyte cells. 8 experimental groups were formed in the study. The cell culture medium was supplemented with 0.16 μg/ml CP and the cells were treated with 50, 100 and 250 μM T. polium and R. crispus extracts in the presence and absence of CP. As a result, CP significantly decreased MI frequency while increasing SCE, MN and NAs frequencies in cells. 100 μM T. polium plus CP decreased SCEs when compared with CP alone. In addition, MN frequency was significantly decreased in 100 μM T. poliumplus CP and 250 μM R. crispus plus CP combine groups. Our results suggest that these plant extracts are not genetically damaging and have improving effects at these doses.

RNA interference plays a major role in biology of ciliates. Diverse small RNAs regulate many processes in vegetative cells of ciliates Tetrahymena and Paramecium. Different types of endogenous and exogenous nucleotide sequences induce different RNAi pathways resulting in silencing of the homologous sequences in the macronuclear genome. Likely this way ciliates are able to quickly inactivate heterogeneous sequences and to adapt efficiently to the environmental conditions and external stimuli.