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Correlation between bilayer destabilization and activity enhancement by diacylglycerols in reconstituted Ca-ATPase vesicles 总被引:1,自引:0,他引:1
Using the reconstituted Ca-ATPase vesicles as a model system, we demonstrated that the presence of 1,2-dioleoyl-sn-glycerol (diolein) in the membrane introduces a pronounced enhancement in the Ca-transport function of Ca-ATPase, while the 1,2-dipalmitoyl-sn-glycerol (dipalmitin) does not. We also found by both 31P NMR and freeze-fraction electron microscopy that diolein destabilized lipid bilayers to a greater extent than did dipalmitin. We conclude that the tendency of diacylglycerols to destabilize the phospholipid bilayer is related to their capacity to enhance the activity of the membrane calcium pump. 相似文献
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Yang Su-Rong Sun Huan-Xin Hu Zhen-Zhen Wang Si-Heng Sun Hui Xue Yin-Jia Ye Chen-Bo 《Sleep and biological rhythms》2017,15(1):57-65
Sleep and Biological Rhythms - Chronic sleep deprivation (SD) is an overwhelming problem in young students. Firstly, we investigated whether different levels of pre-training SD had effects on... 相似文献
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<正>Nanozymes, nanomaterials with enzyme-like characteristics,are emerging as novel artificial enzymes (Gao et al., 2007;Manea et al., 2004; Yan, 2018). They are superior to natural enzymes in many ways, such as higher stability, lower cost in preparation, and better robustness toward harsh environments (Wei and Wang, 2013). Various nanomaterials (e.g., 相似文献
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Most of the previous studies on the effects of iron deficiency on skeletal muscle respiratory capacity and work performance have been investigated in severe or moderate iron-deficiency anemia. We report here that even in mild iron deficiency where the hemoglobin concentration was 10 g/dl and the iron stores in livers and spleen were not completely depleted, a marked reduction in succinate dehydrogenase was observed in skeletal muscles but not in heart. Similarly, cytochrome oxidase activities were reduced. Although no significant change in glycerophosphate dehydrogenase was detected in the iron-deficient rats, exposure to cold in this group greatly reduced this enzyme activity. As cold acclimatization accelerates marrow erythropoiesis (20) which in turn, demands more iron, it seems that in the iron-insufficient state, this iron demand for marrow activity may persist at the expense of the tissue iron pool, resulting in a marked reduction in glycerophosphate dehydrogenase activities. Since succinate dehydrogenase plays a significant role in the impairment of mitochondrial function and early fatigue of iron-deficient muscle (11), the present study shows that even in mild iron deficiency, some loss of muscle functions could result as succinate dehydrogenase activities were greatly reduced. 相似文献