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Botryococcus braunii (N-836) produced 60 – 73% hydrocarbons on dry weight basis, of which C34 botryococcene was found to be the major hydrocarbon, constituting about 50 – 76 % of total content throughout the experimental studies. Major fatty acids present in this organism were C18:1 and C16:0. Saturated hydrocarbons like docosane, hexacosane and heptacosane were also found to be produced by the organism. Methyl branched fatty acids, were identified as 16-methyl heptadecanoic and 5, 9, 13 - trimethyl tetradecanoic acids by GC-MS. Maximum hydrocarbon accumulation was observed during third week of its growth.  相似文献   
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Antifreeze proteins (AFPs) are a group of proteins that protect organisms from deep freezing temperatures and are expressed in vertebrates, invertebrates, plants, bacteria, and fungi. The nuclear magnetic resonance, x-ray structure, and many spectroscopic studies with AFPs have been instrumental in determining the structure–function relationship. Mutational studies have indicated the importance of hydrophobic residues in ice binding. Various studies have pointed out that the mechanism of AFP action is through its adsorption on the ice surface, which leads to a curved surface, preventing further growth of ice by the “Kelvin effect.” The AFPs have potential industrial, medical, and agricultural application in different fields, such as food technology, preservation of cell lines, organs, cryosurgery, and cold hardy transgenic plants and animals. However, the applications of AFPs are marred by high cost due to low yield. This review deals with the source and properties of AFPs from an angle of their application and their potential. The possibility of production using different molecular biological techniques, which will help increase the yield, is also dealt with.  相似文献   
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The chelating behavior of 2,6-diacetylpyridine bis(2-aminobenzoylhydrazone) (H2dapa) towards manganese(II), cadmium(II) and oxovanadium(IV) ions has been studied by elemental analyses, conductance measurements, magnetic properties and spectral (IR, 1H NMR, UV-Vis and EPR) studies. The IR spectral studies suggest the pentadentate nature of the ligand with pyridine nitrogen, two azomethine nitrogens and two carbonyl oxygen atoms as the ligating sites. Six coordinate structure for [VO(H2dapa)]SO4 · H2O and seven coordinate structures for [Mn(H2dapa)(Cl)(H2O)]Cl · 2H2O and [Cd(H2dapa)Cl2] · H2O complexes have been proposed. Pentagonal bipyramidal geometry for [Mn(H2dapa)(Cl)(H2O)]Cl · 2H2O and [Cd(H2dapa)(Cl2)] · H2O complexes was confirmed by single crystal analysis. The X-band EPR spectra of the oxovanadium(IV) and manganese(II) complexes in the polycrystalline state at room (300 K) and also at liquid nitrogen temperature (77 K) were recorded and their salient features are reported.  相似文献   
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Lectin-like molecules and their receptors are cell surface molecules that have been shown to play a role in either facilitating infection or serving as transporters of HIV/SIV in vivo. The role of these lectin-like molecules in the pathogenesis of HIV/SIV infection continues to be defined. In efforts to gain further insight on the potential role of these lectin-like molecules, our laboratory generated monoclonal antibodies (mAb) against the human analogs of rhesus macaque CD200, CD200R and Mincle, since the rhesus macaques are accepted as the most reliable animal model to study human HIV infection. The characterization of the cell lineages from the blood and various tissues of rhesus macaques that express these lectin-like molecules are described herein. Among the mononuclear cells, the cells of the myeloid lineage of rhesus macaques are the predominant cell lineages that express readily detectable levels of CD200, CD200R and Mincle that is similar to the expression of Siglec-1 and Siglec-3 reported by our laboratory earlier. Subset analysis revealed that a higher frequency of the CD14+/CD16- subset from normal rhesus macaques express CD200, CD200R and Mincle. Differences in the frequencies and density of expression of these molecules by the gated population of CD14+ cells from various tissues are noted with PBMC and bone marrow expressing the highest and the mononuclear cells isolated from the colon and ileum expressing the lowest levels. While a significant frequency of pDCs and mDCs express Siglec-1/Siglec-3, a much lower frequency expresses CD200, CD200R and Mincle in PBMCs from rhesus macaques. The mAb against CD200 and CD200R but not Mincle appear to inhibit the infection of macrophage tropic SIV/SHIV in vitro. We conclude that these mAbs may have potential to be used as adjunctive therapeutic agents to control/inhibit SIV/HIV infection.  相似文献   
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Alzheimer’s disease (AD) is a neurodegenerative disorder affecting 35 million people worldwide. A common strategy to improve the well-being of AD patients consists on the inhibition of acetylcholinesterase with the concomitant increase of the neurotransmitter acetylcholine at cholinergic synapses. Two series of unreported N-benzylpiperidines 5(ah) and thiazolopyrimidines 9(aq) molecules were synthesized and evaluated in vitro for their acetylcholinesterase (AChE) inhibitory activities. Among the newly synthesized compounds, 5h, 9h, 9j, and 9p displayed higher AChE enzyme inhibitory activities than the standard drug, galantamine, with IC50 values of 0.83, 0.98, and 0.73 μM, respectively. Cytotoxicity studies of 5h, 9h, 9j, 9n and 9p on human neuroblastoma cells SH-SY5Y, showed no toxicity up to 40 μM concentration. Molecular docking simulations of the active compounds 5h and 9p disclosed the crucial role of π-π-stacking in their binding interaction to the active site AChE enzyme. The presented compounds have potential as AChE inhibitors and potential AD drugs.  相似文献   
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Crimean-Congo hemorrhagic fever (CCHF) virus is one among the major zoonosis viral diseases that use the Hyalomma ticks as their transmission vector to cause viral infection to the human and mammalian community. The fatality of infectious is high across the world especially in Africa, Asia, Middle East, and Europe. This study regarding codon usage bias of S, M, and L segments of the CCHF virus pertaining to the host Homo sapiens, reveals in-depth information about the evolutionary characteristics of CCHFV. Relative Synonymous Codon Usage (RSCU), Effective number of codons (ENC) were calculated, to determine the codon usage pattern in each segment. Correlation analysis between Codon adaptation index (CAI), GRAVY (Hydrophobicity), AROMO (Aromaticity), and nucleotide composition revealed bias in the codon usage pattern. There was no strong codon bias found among any segments of the CCHF virus, indicating both the factors i.e., natural selection and mutational pressure shapes the codon usage bias.  相似文献   
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