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Elevated substrate salinity and anthropogenic impulse are the major threat to the mangrove ecosystem. In the Indian subcontinent, Sundarbans have the richest mangrove species diversity. Due to geomorphic characteristics and unplanned management, the elevated salinity prevails in the western part and that has direct impact on vegetation. Seven mangrove taxa were examined, of which four (Aegialitis rotundifolia, Heritiera fomes, Xylocarpus granatum, and X. mekongensis) were considered as degrading and three (Bruguiera gymnorrhiza, Excoecaria agallocha, and Phoenix paludosa) were considered as natural control. The targeted taxa were collected from five different islands and were selected on the basis of increasing salinity gradient. As salinity increased from site I to V (11.76–15.2 ppt), the amount of total leaf proteins decreased in all the targeted species and ranged between 5.67 and 25.23%. The percentage of protein depletion was less in Aegialitis, Heritiera, and Xylocarpus than the other three taxa in higher salinity that pointed out their less adaptability, as degradation of protein may be essential for efficient stress management. Two antioxidative (peroxidase and superoxide dismutase) and two hydrolyzing (acid phosphatase and esterase) enzymes showed a positive correlation with salinity. In four degrading taxa, the percentage of enzyme increment was less than those of their natural control taxa. Salinity imposed increment of antioxidant enzymes facilitate ROS scavenging, which is an inevitable elevated byproduct during photo-inhibition. Lower amount and number of isoforms in higher salinity indicated towards less suitability of Aegialitis rotundifolia, Heritiera fomes, Xylocarpus granatum, and X. mekongensis in increased salinity level of western Sundarbans.  相似文献   
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The distribution of cyclo(His-Pro), thyrotropin-releasing hormone (TRH) and Pyroglutamate aminopeptidase activity in adult and developing rat brains were studied. A comparison of the subcellular distribution of Pyroglutamate aminopeptidase activity in hypothalamic and cerebral cortical extracts from adult rats exhibited remarkable differences. In hypothalamus, the enzyme activity was mainly associated with the soluble fraction whereas in cortex it was predominantly associated with the particulate fractions. During postnatal development, the brain concentrations of cyclo(His-Pro) and Pyroglutamate aminopeptidase activities declined with age. These data suggest that Pyroglutamate aminopeptidase activity, but not TRH, plays an active role in determining the levels of endogenous cyclo(His-Pro) concentrations in brain.  相似文献   
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The distribution of cyclo (His-Pro)-like immunoreactivity in frog skins from seven frog species was examined. The chromatographic elution profile of cyclo (His-Pro)-like immunoreactivity in amphibian skins measured by radioimmunoassay corresponded precisely to that of [3H-Pro]-cyclo (His-Pro) after DEAE-Cellulose, Sephadex G-25 and high-pressure liquid chromatography. The concentrations of cyclo (His-Pro) in frog skins were much higher than the concentrations of TRH previously observed in skin and the concentrations of cyclo (His-Pro) in both brain and gastrointestinal tract.  相似文献   
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Biological Trace Element Research - Non-enzymatic glycation of lens proteins and elevated polyol pathway in the eye lens have been the characteristic features of a diabetic condition. We have...  相似文献   
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