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11.
转基因烟草感染马铃薯Y病毒脉坏死株系后某些酶活性变化的比较研究 总被引：1，自引：0，他引：1
烟草感染马铃薯Y病毒脉坏死株系后,过氧化物酶活性升高,但非转基因敏感烟草升高的幅度大于转基因抗病烟草;同时,非转基固敏感烟草的苯丙氨酸解氨酶和多酚氧化酶活性均增高,并且都出现两个活性高峰,但转基因抗病烟草的苯丙氨酸解氨酶活性仅出现第一个活性高峰,随后其活性值降低并逐渐恢复至未接种时的水平,而多酚氧化酶活性则降低;在未感染PVYN的情况下,转基因抗病烟草的过氧化物酶、苯丙氨酸解氨酶和多酚氧化酶活性均比非转基因敏感烟草高． 相似文献
12.
细胞色素c是一种广泛存在在细胞线粒体中的富电子蛋白。它在与纳米材料相互作用的过程中引发自由基的生成,扩大纳米材料的生物毒性。为了在分子尺度上理解其与纳米材料的相互作用,通过分子动力学模拟研究细胞色素c与富勒烯衍生物体系（富勒醇、三丙二酸富勒烯）。分析吸附后体系的能量、均方回转半径、接触原子数以及细胞色素c中的Fe原子到富勒烯衍生物质量中心的距离,进而揭示细胞色素c与富勒烯衍生物相互作用机理。 相似文献
13.
Jinxing Chen Xiliang Zheng Jiaxin Zhang Qian Ma Zhiwei Zhao Liang Huang Weiwei Wu Ying Wang Jin Wang Shaojun Dong 《国家科学评论(英文版)》2022,9(3)
Designing highly active nanozymes for various enzymatic reactions remains a challenge in practical applications and fundamental research. In this work, by studying the catalytic functions of natural NADH oxidase (NOX), we devised and synthesized a porous carbon-supported cobalt catalyst (Co/C) to mimic NOX. The Co/C can catalyze dehydrogenation of NADH and transfers electrons to O2 to produce H2O2. Density functional theory calculations reveal that the Co/C can catalyze O2 reduction to H2O2 or H2O considerably. The Co/C can also mediate electron transfer from NADH to heme protein cytochrome c, thereby exhibiting cytochrome c reductase-like activity. The Co/C nanoparticles can deplete NADH in cancer cells, induce increase of the reactive oxygen species, lead to impairment of oxidative phosphorylation and decrease in mitochondrial membrane potential, and cause ATP production to be damaged. This ‘domino effect’ facilitates the cell to approach apoptosis. 相似文献
14.
大量研究证实血红素蛋白或NAD(P)H氧化酶是缺氧感受器，并由此引起一系列缺氧的信号传导过程，包括cAMP、Ca^2 、NO、CO、cGMP等信使分子的参与，最终激活缺氧诱导因子—1(HIF—1)使机体产生缺氧反应。还有人认为线粒体参与这一过程，而且可能是缺氧感受器，此外，HIF—1和缺氧反应基因(HRG)的转录调控机制也参与了缺氧过程。 相似文献
15.
关于运动性疲劳的氧自由基——脂质过氧化理论概述 总被引：16，自引：0，他引：16
张雪琳 《河北体育学院学报》2000,(3)
对氧自由基、脂质过氧化反应引起的运动性疲劳的产生机制、诊断方法及有效的消除措施进行综述。 相似文献
16.
南果梨果皮、果肉、果心多酚氧化酶同工酶的研究 总被引：3，自引：0，他引：3
用垂直板聚丙烯酰胺凝的方法,研究了南果梨果皮、果肉、果心的多酚氧化酶同工酶的酶带特征.结果表明:采用pH6.5磷酸缓冲液提取液、10%分离胶浓度对南果梨多酚氧化酶同工酶分离效果较好;南果梨果皮部位多酚氧化酶同工酶谱带最多,为7条. 相似文献
17.
Jagannath G. Satav Surendra S. Katyare 《Indian journal of clinical biochemistry : IJCB》2004,19(2):23-31
The reports in the literature on effects of diabetes on mitochondrial energy-linked functions are conflicting. Hence we carried
out systematic studies to evaluate the effects at the early and the late stages of the disease using STZ-diabetic rat as a
model. At the end of one week, after induction of diabetes, respiration rates with glutamate and succinate as the substrates
increased; respiration rates with other substrates e.g. β-hydroxybutyrate, pyruvate + malate and ascorbate + TMPD were not
affected despite substantial decrease in the β-hydroxybutyrate dehydrogenase activity and cytochrome b and c+c1 contents. Insulin treatment brought about increase in the cytochrome contents beyond control values. The ATPase activity
was generally low in the diabetic animals and was not restored by insulin treatment.
At the end of one month, the respiratory activities with all the substrates were generally low. Insulin treatment either restored
or stimulated the respiration rates beyond control values. The content of cytochromes was differentially affected in the diabetic
animals, but insulin treatment caused significant increase beyond control levels. The pattern for ATPase activity was similar
to the early effects.
At both the stages i.e. early and late stages of diabetes the mitochondria were tightly coupled. The ADP/O ratios were in
normal expected ranges and the respiratory control ratios were comparable with the control groups. Insulin treatment resulted
in apparent restoration of respiratory activity. However, the effects on the cytochromes and dehydrogenases activities were
differential. Taken together the two observations would suggest that the mitochondria were not re-instated to normality despite
apparent restoration of respiratory function. 相似文献
18.
最近研究表明天然维生素E能激活PXR受体,调控其下游靶基因CYP3A及MDR1的表达.而临床上50%的药物是通过CYP3A代谢,P-糖蛋白能转运大部分的抗生素,抗疟药,肿瘤化疗药物,CYP3A与P-糖蛋白底物及调控机制均相似,两者共同抵御外界化学物质进入细胞.在药物联合使用中天然维生素E很有可能影响其它药物代谢,产生药物相互作用.由P-糖蛋白或CYP3A代谢的药物与天然维生素E同时服用,可能会因为天然维生素E影响了CYP3A或P-糖蛋白的活性而产生药物相互作用.导致不良反应. 相似文献
19.
20.
Shu-na Yuan Malik Waqas Shui-jin Hua Noreen Bibi Xue-de Wang 《Journal of Zhejiang University. Science. B》2012,13(6):478-486
Colored cotton has naturally pigmented fibers. The mechanism of pigmentation in cotton fiber is not well documented. This experiment was conducted to study the effects of respiratory chain inhibitors, i.e., rotenone and thiourea, on pigmentation and fiber development in colored cotton. After 1 d post-anthesis, ovaries were harvested and developing ovules were cultured on the liquid medium containing different concentrations of rotenone and thiourea for 30 d. The results demonstrate that both respiratory inhibitors reduced fiber length and ovule development under ovule culture conditions, and the inhibition efficiency of rotenone was much higher than that of thiourea. Rotenone and thiourea also showed significant effects on fiber pigment (color) development in colored cotton. In green cotton fiber, rotenone advanced fiber pigment development by 7 d at 200 μmol/L, while thiourea inhibited fiber pigmentation at all treatment levels (400, 600, 800, 1 000, and 2 000 μmol/L). Both respiratory inhibitors, however, had no significant effects on pigmentation of brown cotton fibers. The activities of cytochrome c oxidase (COX) and polyphenol oxidase (PPO) decreased significantly with increasing levels of both respiratory inhibitors. It is suggested that both respiratory inhibitors have important roles in deciphering the mechanism of pigmentation and fiber development in colored cotton. 相似文献