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Reviews in Environmental Science and Bio/Technology - The world’s energy system is still dominated by fossil fuels. While there is a rapid reduction in the cost of renewable energy and the...  相似文献   
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Molecular Biology Reports - Plant-derived phytochemicals such as flavonoids have been explored to be powerful antioxidants that protect against oxidative stress-related diseases. In the present...  相似文献   
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Infection of human cells by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV2) relies on its binding to a specific receptor and subsequent fusion of the viral and host cell membranes. The fusion peptide (FP), a short peptide segment in the spike protein, plays a central role in the initial penetration of the virus into the host cell membrane, followed by the fusion of the two membranes. Here, we use an array of molecular dynamics simulations that take advantage of the highly mobile membrane mimetic model to investigate the interaction of the SARS-CoV2 FP with a lipid bilayer representing mammalian cellular membranes at an atomic level and to characterize the membrane-bound form of the peptide. Six independent systems were generated by changing the initial positioning and orientation of the FP with respect to the membrane, and each system was simulated in five independent replicas, each for 300 ns. In 73% of the simulations, the FP reaches a stable, membrane-bound configuration, in which the peptide deeply penetrated into the membrane. Clustering of the results reveals three major membrane-binding modes (binding modes 1–3), in which binding mode 1 populates over half of the data points. Taking into account the sequence conservation among the viral FPs and the results of mutagenesis studies establishing the role of specific residues in the helical portion of the FP in membrane association, the significant depth of penetration of the whole peptide, and the dense population of the respective cluster, we propose that the most deeply inserted membrane-bound form (binding mode 1) represents more closely the biologically relevant form. Analysis of FP-lipid interactions shows the involvement of specific residues, previously described as the “fusion-active core residues,” in membrane binding. Taken together, the results shed light on a key step involved in SARS-CoV2 infection, with potential implications in designing novel inhibitors.  相似文献   
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Kenaf (Hibiscus cannabinus L.) and roselle (H. sabdariffa L.) are valuable fibre crop species with diverse end use. Phylogenetic relationship of 73 accessions of kenaf, roselle and their wild relatives from 15 countries was assessed using 44 inter-simple sequence repeat (ISSR) and jute (Corchorus olitorius L.) specific simple sequence repeats (SSR) markers. A total of 113 alleles were identified of which 61.95 % were polymorphic. Jute specific SSR markers exhibited high polymorphism and resolving power in kenaf, although ISSR markers exhibited higher resolving power than SSR markers. Number of polymorphic alleles varied from 1 to 5 for ISSR and 1 to 6 for SSR markers. Cultivated species exhibited higher allele polymorphism (57 %) than the wild species (35 %), but the improved cultivars exhibited lower genetic diversity compared to germplasm accessions. Accessions with common genetic lineage and geographical distribution clustered together. Indian kenaf varieties were distinct from cultivars bred in other countries and shared more genetic homology with African accessions. High genetic diversity was observed in the Indian (J = 0.35–0.74) and exotic kenaf germplasm collections (J = 0.38–0.79), suggesting kenaf might have been introduced in India from Africa through Central Asia during early domestication. Genetic similarity-based cluster analysis was in close accordance with taxonomic classification of Hibiscus.  相似文献   
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Irisin was first identified in muscle cells. We detected irisin immunoreactivity in various organs of the crested porcupine (Hystrix cristata). In the epidermis, irisin immunoreactivity was localized mainly in stratum basale, stratum spinosum and stratum granulosum layers; immunoreactivity was not observed in the stratum corneum. In the dermis, irisin was found in the external and internal root sheath, cortex and medulla of hair follicles, and in sebaceous glands. Irisin immunoreactivity was found in the neural retina and skeletal muscle fibers associated with the eye. The pineal and thyroid glands also exhibited irisin immunoreactivity.  相似文献   
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A chronological relationship between the annual profiles of oxidative stress markers, the key regulator of stress physiology has been sought in a terrestrial mollusc (Nerita articulata) under natural photothermal conditions. The hemolymph samples were collected at two different times in each month (from January to December) and the same was repeated for two consecutive years throughout an annual cycle. The fluctuations in the concentrations of certain heavy and trace metals (zinc, copper, cadmium, mercury, lead, and nickel) in both soil and hemolymph of Nerita are also estimated accordingly. Therefore, the present study aims to explore the rhythmic responses of oxidative stress marker to assess the impact of different trace and heavy metals on selected mollusc species. We tries to develop a realistic conceptual idea to analyze and predict the effect of changing environmental pollution on the possible shift in the rhythmicity of aforesaid antioxidants in terrestrial mollusc and their adaptive responses to thrive in such environment. Our results indicates that the amplitude of circannual rhythms of all the selected stress markers varied accordingly but the pattern of annual fluctuation is noted to be similar, and correlated with the metal accumulation. Therefore current information might help to frame the adaptive strategies for invertebrate species under similar toxic circumstances.  相似文献   
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