Impact of mineral fertilizers on mineral nutrients in the ginger rhizome and on soil enzymes activities and soil properties

Ginger is used as one of the important ingredients in traditional as well as modern medicine besides as a spice. It boosts immunity and is a rich source of many biologically active substances and minerals. Although it is a medicinally important crop, its productivity is, however, affected due to poor nutrient management and therefore it requires an adequate supply of nutrients in the form of inorganic fertilizers or organic manuring, or a mixture of both. In this context, the present study was aimed to investigate the effect of mineral fertilizers on the content of mineral elements in the ginger rhizome, on soil enzyme activity, and soil properties. Lysimeter experiments were conducted at the Institute of Genetics and Plant Experimental Biology, Kibray, Tashkent region, Uzbekistan. The experiment comprised of four treatments T1 – Control, T2 - N₇₅P₅₀K₅₀ kg/ha, T3 - and T4 - N₁₀₀P₇₅K₇₅ + B₃Zn₆Fe₆ kg/ha. The results showed that the application of N₁₂₅P₁₀₀K₁₀₀ kg/ha increased rhizome K content by 49%, P content by 20%, and Na content by 58% as compared to control without fertilizer. While the application of N₁₀₀P₇₅K₇₅ + B₃Zn₆Fe₆ kg/ha showed a significant enhancement in rhizome K, Ca, P, Mg, Na, Fe, Mn, Zn, Cu, Cr, Mo, and Si contents over the control. This treatment also improved active P content by 29%, total P content by 80%, total K content 16%, and N content by 33% content, and the activities of urease, invertase, and catalase activities as compared to control of without mineral fertilizer and control respectively. Thus the application of NPK + BZnFe at the rate of 100:75:75:3:6:6 kg/ha helps in improving macroelements and microelements in the ginger rhizome and activities of soil enzymes that helps in mineral nutrition of the rhizome.     

Novel Interactions of CAPS (Ca2+-dependent Activator Protein for Secretion) with the Three Neuronal SNARE Proteins Required for Vesicle Fusion

CAPS (aka CADPS) is required for optimal vesicle exocytosis in neurons and endocrine cells where it functions to prime the exocytic machinery for Ca²⁺-triggered fusion. Fusion is mediated by trans complexes of the SNARE proteins VAMP-2, syntaxin-1, and SNAP-25 that bridge vesicle and plasma membrane. CAPS promotes SNARE complex formation on liposomes, but the SNARE binding properties of CAPS are unknown. The current work revealed that CAPS exhibits high affinity binding to syntaxin-1 and SNAP-25 and moderate affinity binding to VAMP-2. CAPS binding is specific for a subset of exocytic SNARE protein isoforms and requires membrane integration of the SNARE proteins. SNARE protein binding by CAPS is novel and mediated by interactions with the SNARE motifs in the three proteins. The C-terminal site for CAPS binding on syntaxin-1 does not overlap the Munc18-1 binding site and both proteins can co-reside on membrane-integrated syntaxin-1. As expected for a C-terminal binding site on syntaxin-1, CAPS stimulates SNARE-dependent liposome fusion with N-terminal truncated syntaxin-1 but exhibits impaired activity with C-terminal syntaxin-1 mutants. Overall the results suggest that SNARE complex formation promoted by CAPS may be mediated by direct interactions of CAPS with each of the three SNARE proteins required for vesicle exocytosis.     

Active site of α1-antitrypsin: Homologous site in antithrombin-III

Examination of peptides resulting from reaction of bovine trypsin and human α₁-antitrypsin in near-equimolar amounts showed anomalous cleavage of antitrypsin at a Met-Ser bond 37 residues from the C-terminus, giving evidence that this is the active site for trypsin inhibition. Alignment of the C-terminal 141 residues of α₁-antitrypsin with the C-terminal 147 residues of human antithrombin-III showed homology with 30% identity and allowed the identification of a homologous active site in antithrombin.     

The effects of a diet rich in docosahexaenoic acid on organ and vascular fatty acid composition in spontaneously hypertensive rats

Previous research has shown that dietary docosahexaenoic acid (DHA) attenuates the development of high blood pressure in young spontaneously hypertensive rats (SHR). The purpose of this study was to investigate the effects of dietary DHA on organ and vascular fatty acid composition in SHR. Given the important structural and functional role of fatty acids in cell membranes, alterations in fatty acid composition may contribute to the antihypertensive effect of DHA. SHR were fed a purified diet containing either a corn/soybean oil mixture (CSO, control) or a DHA-enriched oil for 6 weeks. The DHA diet markedly increased the levels of DHA in the aorta, renal artery, plasma, liver, heart, kidney, and lung by 5-, 15-, 7-, 6-, 3.8-, 3.5-, and 8.8-fold (P<0.001), respectively. The levels of eicosapentaenoic acid were also increased while there was a concomitant reduction in arachidonic and adrenic acids. Therefore, dietary DHA increases the incorporation of omega-3 polyunsaturated fatty acids in specific organs and vascular tissue in SHR at the expense of omega-6 polyunsaturated fatty acids.     

Global defects in the expression and function of the low density lipoprotein receptor (LDLR) associated with two familial hypercholesterolemia mutations resulting in misfolding of the LDLR epidermal growth factor-AB pair

The low density lipoprotein (LDL) receptor is a modular protein involved in the endocytosis of cholesterol-rich lipoproteins from the circulation. Mutations to the receptor result in familial hypercholesterolemia, and over 60 of these occur in the calcium-binding epidermal growth factor-like domain pair. Two selected mutations in this region (G322S and R329P) were introduced into the domain pair and analyzed by in vitro refolding. Both exhibited differing levels of protein misfolding with R329P being the most pronounced. Solution NMR studies of the mutant domain pairs after purification established that a fraction of protein maintains a native-like fold and that this fraction contains two intact calcium-binding sites. An in vivo analysis of intact receptors containing these binding sites showed significantly reduced cell-surface expression compared with the native LDL receptor levels, again with R329P showing the most severe decrease. The sum of these results suggests that either local changes in structure or domain misfolding may be associated with the mutations. There is also the possibility that the misfolding of the calcium-binding epidermal growth factor-like pair region is propagated to other regions of the intact receptor, resulting in more global defects. Surprisingly, for both mutants, those full-length receptors that fold and reach the cell surface retain the ability to bind LDL and release the ligand upon exposure to low pH. This analysis provides significant insight into the protein defect resulting from each of the two mutations and allows their classification to be 2B (partially transport-defective). The results also highlight a range of misfolding defects that may be associated with familial hypercholesterolemia and may enable the prediction of the consequences of homologous disease-causing mutations to other proteins.     

Identification of Kluyveromyces lactis Telomerase: Discontinuous Synthesis along the 30-Nucleotide-Long Templating Domain

Telomeres in the budding yeast Kluyveromyces lactis consist of perfectly repeated 25-bp units, unlike the imprecise repeats at Saccharomyces cerevisiae telomeres and the short (6- to 8-bp) telomeric repeats found in many other eukaryotes. Telomeric DNA is synthesized by the ribonucleoprotein telomerase, which uses a portion of its RNA moiety as a template. K. lactis telomerase RNA, encoded by the TER1 gene, is ~1.3 kb long and contains a 30-nucleotide templating domain, the largest ever examined. To examine the mechanism of polymerization by this enzyme, we identified and analyzed telomerase activity from K. lactis whole-cell extracts. In this study, we exploited the length of the template and the precision of copying by K. lactis telomerase to examine primer elongation within one round of repeat synthesis. Under all in vitro conditions tested, K. lactis telomerase catalyzed only one round of repeat synthesis and remained bound to reaction products. We demonstrate that K. lactis telomerase polymerizes along the template in a discontinuous manner and stalls at two specific regions in the template. Increasing the amount of primer DNA-template RNA complementarity results in stalling, suggesting that the RNA-DNA hybrid is not unpaired during elongation in vitro and that lengthy duplexes hinder polymerization through particular regions of the template. We suggest that these observations provide an insight into the mechanism of telomerase and its regulation.     

Leaf temperature of desert sand dune plants: perspectives on the adaptability of leaf morphology

The leaf temperature of six annual and six perennial plant species was monitored during spring and summer on a sand dune ecosystem in the delta Mediterranean coast of Egypt. During winter, leaves of all tested perennial species attained temperatures higher than the air temperature at night and shortly after sunrise, with maximum leaf–air temperature differences reaching up to 8°C. The lowest differences were less than 1°C. Around noon, the leaves of several species attained temperatures lower than that of the air whereas others showed higher temperatures. The opposite was true during summer, when leaf temperatures were lower than air temperature. The maximum leaf–air temperature differences occurred after midnight towards sunrise and reached up to 10°C. The lowest differences were found around noon and were of less than 5°C. The annual plant species have more pronounced variations than perennials in their leaf temperatures during the night and for most of the day. The leaves were heated or cooled a few degrees above or below the air temperature. The results are discussed in relation to the morphological characters of the leaves. The variation in leaf temperature at different times of the day was significantly related to leaf morphology, specific leaf area, thickness, volume, leaf area index and the surrounding environment.     

Plant-soil relationships in a New Caledonian serpentine flora

Summary Elemental concentrations were studied in two New Caledonian hyper-accumulators of nickel and in the soils supporting these plants. The nickel content of Hybanthus austrocaledonicus was directly related to the total nickel content of the soil, and this species may therefore be used for biogeochemical prospecting. Nickel was correlated well with other elements of the iron family in non-lateritic ultrabasic soils but not in laterites. Both H. austrocaledonicus and Homalium kanaliense contained adequate amounts of potassium despite very low concentrations in the supporting soils. These low nutrient levels were further aggravated by antagonism to potassium uptake caused by other soil elements. Because of the paucity of relationships between nickel in H. kanaliense and elements in the soil, it is suggested that the high nickel levels in this plant may be controlled by organic constituents in this species. re]19760504