Protein expression of Yersinia pestis during changes due to long-term cultivation in vivo]

The electrophoretic study of Yersinia pestis proteins made possible to find the significant modification of Yersinia pestis polypeptide specters when the bacteria were cultivated in semi-penetrable cells implanted into the guinea pigs peritoneum. The proteinogramms of the isolates from the implanted cells lacked the stained bands characteristic of Yersinia pestis cells grown in vitro and contained the new polypeptides absent from the bacteria grown on the Hottinger agar plates. The difference was found at the late stage of bacteria incubation in implanted cells and had the predominantly reversible characteristics. The protein of Yersinia pestis being changed in vivo is proposed to be the species specific fraction I.     

Functional Condition of Photosystem II in Leaves of Spring Oats during Autumnal Decrease in Temperature

Russian Journal of Plant Physiology - Dynamics of chlorophyll a fluorescence changes (including JIP test parameters) and photosynthetic pigments were studied in oat (Avena sativa L.) leaves of late...     

A correlation between BCL-2 modifying factor,p53 and livin gene expressions in cancer colon patients

Accumulating evidence has revealed that livin gene and BCL-2 modifying factor (BMF) gene are closely associated with the initiation and progression of colon carcinoma by activating or suppressing multiple malignant processes. Those genes that can detect colon - cancer are a promising approach for cancer screening and diagnosis. This study aimed to evaluate correlation between livin, BMF and p53 genes expression in colon cancer tissues of patients included in the study, and their relationship with clinicopathological features and survival outcome in those patients. In this study, 50 pathologically diagnosed early cancer colon patients included and their tissue biopsy with 50 matched adjacent normal tissue, and 50 adenoma tissue specimens were analyzed for livin gene and BMF gene expressions using real time PCR. The relationship of those genes expressions with clinicopathological features, tumor markers, Time to Progression and overall survival for those patients were correlated in cancer colon group. In this study, there was a significant a reciprocal relationship between over expression of livin gene and down regulation of BMF and p53 genes in colon cancer cells. Livin mRNA was significantly higher, while BMF and p53 mRNA were significantly lower in colorectal cancer tissue compared to benign and normal colon tissue specimens (P < 0.001), however, this finding was absent between colon adenomas and normal mucosa. There was a significant association between up regulation of livin and down regulation of BMF and p53 expressions with more aggressive tumor (advanced TNM stage), rapid progression with metastasis and decreased overall survival in cancer colon patients, hence these genes can serve as significant prognostic markers of poor outcome in colon cancer patients. This work highlights the role of livin, BMF and p53 genes in colorectal tumorigenesis and the applicability of using those genes as a diagnostic and prognostic markers in patients with colon carcinoma and as a good target for cancer colon treatment in the future.     

Photosynthetic and Respiratory Capacity of Foliose Lichen Lobaria pulmonaria throughout the Annual Cycle

Russian Journal of Plant Physiology - Lichens are unique phototrophic organisms whose physiology of stress tolerance attracts much attention. Parameters of photosynthetic and respiratory activities...     

Seasonal changes in growth and metabolic activity of underground shoots of yarrow

Growth and metabolic activity of underground shoots of a long-rhizome perennial herbaceous species yarrow (Achillea millefolium L.) were studied. The active growth of rhizomes and the formation of new meristematic zones were observed during the second half of the growing season after termination of aboveground shoot growth. In this period, underground shoots had a rather high rate of respiration (1.3 mg CO₂/(g dry wt h)), a considerable content of nonstructural carbohydrates (15% of dry weight), and the elevated activities of IAA, cytokinins, and ABA. In autumn, the rate of respiration of underground shoots decreased to 1.0 mg CO₂/(g dry wt h), soluble sugars accumulated, the ratio between unsaturated and saturated fatty acids rose as well as the ratios GA/ABA and cytokinins/ABA. Temperature optimum for the rhizome growth lay in the range of low and moderate above-zero temperatures (5–20°C), and the freezing point of water in the apices of under-ground shoots was about ?10°C. It is concluded that rhizome quiescence predominantly depends on low temperatures and is not associated with the accumulation of growth inhibitors. In the course of plant preparation to winter, morphogenetic transformations in underground shoots depend on changes in the hormonal balance directed in favor of growth hormones and relatively high respiratory activity in the apical zones of the rhizomes.     

Biocides formulation of essential oils having antimicrobial activity

Essential oils of fennel, peppermint, caraway, eucalyptus, geranium and lemon were tested for their antimicrobial activities against some plant pathogenic micro-organisms (Fusarium oxysporum, Alternaria alternate, Penicilium italicum Penicilium digitatum and Botyritus cinerea). Essential oils of fennel, peppermint, caraway were selected as an active ingredient for the formulation of biocides due to their efficiency in controlling the tested micro-organisms. Successful emulsifiable concentrates (biocides) were prepared from these oils using different emulsifiers (Emulgator B.L.M. Tween20 and Tween80) and different fixed oils (sesame, olive, cotton and soybean oils). Physico-chemical properties of the formulated biocide (spontaneous emulsification, emulsion stability test, cold stability and heat stability tests as well as viscosity, surface tension and pH) were measured. The prepared biocides were ready to be tested for application in a future work as a safe pesticide against different pathogens.     

Metagenomic insights into strategies of carbon conservation and unusual sulfur biogeochemistry in a hypersaline Antarctic lake

Organic Lake is a shallow, marine-derived hypersaline lake in the Vestfold Hills, Antarctica that has the highest reported concentration of dimethylsulfide (DMS) in a natural body of water. To determine the composition and functional potential of the microbial community and learn about the unusual sulfur chemistry in Organic Lake, shotgun metagenomics was performed on size-fractionated samples collected along a depth profile. Eucaryal phytoflagellates were the main photosynthetic organisms. Bacteria were dominated by the globally distributed heterotrophic taxa Marinobacter, Roseovarius and Psychroflexus. The dominance of heterotrophic degradation, coupled with low fixation potential, indicates possible net carbon loss. However, abundant marker genes for aerobic anoxygenic phototrophy, sulfur oxidation, rhodopsins and CO oxidation were also linked to the dominant heterotrophic bacteria, and indicate the use of photo- and lithoheterotrophy as mechanisms for conserving organic carbon. Similarly, a high genetic potential for the recycling of nitrogen compounds likely functions to retain fixed nitrogen in the lake. Dimethylsulfoniopropionate (DMSP) lyase genes were abundant, indicating that DMSP is a significant carbon and energy source. Unlike marine environments, DMSP demethylases were less abundant, indicating that DMSP cleavage is the likely source of high DMS concentration. DMSP cleavage, carbon mixotrophy (photoheterotrophy and lithoheterotrophy) and nitrogen remineralization by dominant Organic Lake bacteria are potentially important adaptations to nutrient constraints. In particular, carbon mixotrophy relieves the extent of carbon oxidation for energy production, allowing more carbon to be used for biosynthetic processes. The study sheds light on how the microbial community has adapted to this unique Antarctic lake environment.     

Bud dormancy breaking affects respiration and energy balance of bilberry shoots in the initial stage of growth

Respiration and heat production in the shoots of bilberry (Vaccinium myrtillus L.) were studied at the beginning of growth after breaking bud dormancy by means of transfer of the shoots to indoor conditions (November–April) and upon natural sprouting in spring (May). The buds released from dormancy at the beginning of winter sprouted slower and showed lower respiratory activity than the buds that started growing in May. In May, cytochrome respiratory pathway in sprouting buds was 1.3 times more active than energetically ineffective alternative pathway, whereas activity of cytochrome pathway in December was 1.4 times lower as compared with the alternative. In November–December, the rate of heat evolution by the buds was 3–5 times lower than in April–May. In case of early breaking of bud dormancy, the share of respiration energy dissipated as heat was 30% on average. In the buds whose growth was induced later, the value of this parameter was twice as much. The ratio between heat evolution and respiration depended on temperature. High temperature more intensely activated heat evolution than respiration, which caused a decrease in the level of metabolic energy available for growth. In the temperature range of 5–15°C characteristic of the beginning of vegetation, the share of respiration energy dissipated as heat was 2–3 times lower than at 20–30°C, which reflects a great adaptability of V. myrtillus to climatic conditions of the region. Our data suggest that progression through a full cycle of winter dormancy is physiologically important for shoot growth. Early dormancy release brought about changes in respiration and energy balance of the shoots in the initial stage of extra-bud growth.     

Single "early" action potential cause by Ni2+ ions in true pacemaker cells of the sinoatrial ring of the dace heart

Single "early" action potentials (AP) or "early" postdepolarization (EAD) were recorded in multicellular stripes working in the regimen of true pacemaker cells located in the basis of the sinoatrial valve of the dace (Leuciscus rutilus) heart after Ni2+ (0.3 mM) were added to superfused solution on the 15 th min. The standard microelectrode technique was used. The appearance of single EAD was preceded by increase of AP spike duration almost 1.5-fold due to increase of the duration of a final repolarization phase and of diastolic depolarization. EADs appeared at different levels of repolarization from -20 to -60 mV. EAD's amplitude was lower than the AP proper. The effect is reversible. Nifedipine (2 microM) decreased by 20% the AP duration to 50% repolarization in the cells of atrial type. In case the stripes were primarily subjected to nifedipine effect and then even after a long procedure of washout, the Ni2+ (0.3 mM) did not cause EADs. The hypothesis has been tested of what is the main reason of single EAD appearance in pacemaker cells under the effect of Ni2+; it is either blocking Ca release from the cell by Ni2+, or reactivation of L-type Ca-channels' conductivity. The analysis of the data obtained leads to the conclusion that 30-50% Na-Ca-exchangers block is the basic reason of single EAD appearance in pacemaker cells.