The NMR spin-echo method is used for measurements of the translational water diffusion selectively along the apoplast and the vacuolar and cytoplasmic symplasts of plant tissue

Simple methods for the registration of translational diffusion of water in apoplast and vacuolar and cytoplasmic symplasts were developed. The methods are based on spin-echo NMR with a pulsed magnetic field gradient and are realized by preliminary inversion of magnetization and the use of paramagnetic doping. It was shown that the diffusion of a part of root water in segments of mais roots is more enhanced than that for the bulk water. The results are explained by the appearance of the rotational movement of the protoplasm and in terms of the hypothesis of water transfer along the apoplast, which balances the cytoplasmic symplast.     

Reproductive Performance,Udder Health,and Antibiotic Resistance in Mastitis Bacteria isolated from Norwegian Red cows in Conventional and Organic Farming

Background  

The objectives of this study were to investigate whether there were differences between Norwegian Red cows in conventional and organic farming with respect to reproductive performance, udder health, and antibiotic resistance in udder pathogens.     

Mitochondria-addressed cations decelerate the leaf senescence and death in Arabidopsis thaliana and increase the vegetative period and improve crop structure of the wheat Triticum aestivum

Plastoquinone or its methylated form covalently bound to the membrane-penetrating decyltriphenylphosphonium cation (SkQ1 and SkQ3) retarded the senescence of Arabidopsis thaliana rosette leaves and their death. Dodecyltriphenylphosphonium (C₁₂TPP⁺) had a similar effect. Much like SkQ1, C₁₂TPP⁺ prevented production of reactive oxygen species (ROS) measured by the fluorescence of 2′,7′-dichlorofluorescein in mitochondria of the plant cells. SkQ1 augmented the length of the vegetation period and the common and productive tillering, improved the crop structure and the productivity of the wheat Triticum aestivum. These results indicate that the tested compounds act as antioxidants, that ROS participate in aging and death of A. thaliana leaves, and wheat tillering is increased and the crop structure is improved by SkQ1.     

Potential therapeutic drug target identification in Community Acquired-Methicillin Resistant Staphylococcus aureus (CA-MRSA) using computational analysis

The emergence of multidrug-resistant strain of community-acquired methicillin resistant Staphylococcus aureus (CA-MRSA) strain has highlighted the urgent need for the alternative and effective therapeutic approach to combat the menace of this nosocomial pathogen. In the present work novel potential therapeutic drug targets have been identified through the metabolic pathways analysis. All the gene products involved in different metabolic pathways of CA-MRSA in KEGG database were searched against the proteome of Homo sapiens using the BLASTp program and the threshold of E-value was set to as 0.001. After database searching, 152 putative targets were identified. Among all 152 putative targets, 39 genes encoding for putative targets were identified as the essential genes from the DEG database which are indispensable for the survival of CA-MRSA. After extensive literature review, 7 targets were identified as potential therapeutic drug target. These targets are Fructose-bisphosphate aldolase, Phosphoglyceromutase, Purine nucleoside phosphorylase, Uridylate kinase, Tryptophan synthase subunit beta, Acetate kinase and UDP-N-acetylglucosamine 1-carboxyvinyltransferase. Except Uridylate kinase all the identified targets were involved in more than one metabolic pathways of CA-MRSA which underlines the importance of drug targets. These potential therapeutic drug targets can be exploited for the discovery of novel inhibitors for CA-MRSA using the structure based drug design (SBDD) strategy.     

Effect of Water Stress and Mercuric Chloride on the Translational Diffusion of Water in Maize Seedling Roots

Water diffusion in maize roots (Zea mays L., cv. Donskaya 1) was investigated with a pulsed gradient NMR using mercuric chloride as an inhibitor of water channels in cell membranes. A novel operation program was applied that allowed selective evaluation of fractional amounts of water transported through various pathways—the apoplastic, symplasmic, and transmembrane routes. The blockage of water channels with HgCl₂ reduced the rates of water diffusion by a factor of 1.5–2. This effect was reversible and was removed by the addition of -mercaptoethanol. The coefficient of water diffusion changed with time elapsed after the HgCl₂ treatment. The effect of water stress on the rates of water diffusion was similar to that of HgCl₂. Remarkably, the water-stressed roots of maize seedlings were insensitive to the inhibitor of water channels. The results are interpreted in terms of redistribution of water flows among various routes in plant tissues. Water stress and mercuric chloride treatments decelerate the transmembrane water transport and promote water flow along the apoplastic pathway. These responses might arise from the reversible regulation of water movement along various transport pathways.     

Radial diffusion transport of water in various zones of maize root and its sensitivity to mercury chloride

NMR-spin echo method was used for comparative study of radial water diffusion in various zones of maize (Zea mays L., cv. Donskaya 1) primary root. Coefficients of water diffusion varied strongly along the root length; the pattern of variations depended on the period during which the diffusion of water molecules was traced. Water diffusion transport in various root zones was unevently sensitive to mercury chloride, an aquaporin inhibitor. The discovered variations in the mobility of water molecules were assigned to morphological and functional features of cells and tissues in the root zones examined; they were interpreted in terms of variable contribution and redistribution of water flows along several transport pathways. The decrease in diffusional water flows could be caused by cell wall modifications (deposition of suberin) that emerge in the endoderm regions distant from the root apex and diminish the contribution of apoplastic transport.     

Effect of temperature on water transport through aquaporins

The mean effective water self-diffusion coefficient in maize root segments under the effect of aquaporin blocker (mercuric chloride, 0.1 mM) was measured using the spin-echo NMR method with pulsed magnetic field gradient within the temperature range from 10 to 35 °C. HgCl₂ caused the reduction in water diffusion by 30 % as compared to the control samples. Temperature dependences of water self-diffusion coefficients showed two linear regions with different values of Q₁₀ and activation energy, E_a. As the temperature reduced from 20 to 10 °C, E_a values calculated from the Arrhenius plots were close to those of bulk water (20 ± 3 kJ mol⁻¹) and slightly changed for the sample pretreated HgCl₂. Within the temperature range from 25 to 35 °C the slope of temperature dependences became steeper and E_a values were 31 ± 3 kJ mol⁻¹ for the control and 40 ± 4 kJ mol⁻¹ for the treated sample. In the vicinity of 20 °C, the temperature dependence of water diffusion via the mercury-sensitive water channels showed extreme value. In the region, the specific area of the mercury-sensitive aquaporins was 0.004 % of the total cell surface area. The data indicate that water transfer via aquaporins is sensitive to temperature, and the contributions of the transmembrane pathways (aquaporins, lipid bilayer) differ in different temperature ranges.     

Differential sensitivities of water diffusion in maize root cortex and stele to HgCl<Subscript>2</Subscript>-induced blockade of aquaporins

Spin-echo NMR comparative study of water diffusion in the cortex and stele of maize (Zea mays L.) roots was made with the aim to determine predominant pathways of radial water movement in the root. The root parts examined differed in terms of water diffusion coefficients and sensitivity to HgCl₂, the aquaporin blocker. These differences are discussed from the viewpoint of unequal contributions of separate transport pathways (apoplastic, symplastic, and transmembrane) to the overall water flow. Characteristics of water diffusion in roots with the endodermis damaged suggest an inconsiderable contribution of the endodermis into resistance to water movement.     

The RAS subfamily Evolution – tracing evolution for its utmost exploitation

In the development of multicellularity, signaling proteins has played a very important role. Among them, RAS family is one of the most widely studied protein family. However, evolutionary analysis has been carried out mainly on super family level leaving sub family information in scanty. Thus, a subfamily evolutionary study on RAS evolutionary expansion is imperative as it will aid in better drug designing against dreadful diseases like Cancer and other developmental diseases. The present study was aimed to understand RAS evolution on both holistic as well as reductive level. All human RAS family genes and protein were subjected to BLAST tools to find orthologs and paralogs with different parameters followed by phylogenetic tree generation. Our results clearly showed that H-RAS is the most primitive RAS in higher eukaryotes and then diverged into other RAS family members due to different gene modification events. Furthermore, a site specific selection pressure analysis was carried out using SELECTON server which showed that H-RAS, M-RAS and N-RAS are evolving faster than K-RAS and R-RAS. Thus, the results ascertain a new ground to cancer biologists to exploit negatively selected K-RAS and R-RAS as potent drug targets in cancer therapeutics.