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Rukui Zhu Yu Liang Huajian Luo Huishan Cao Yi Liu Shan Huang Qi Xiao 《Journal of molecular recognition : JMR》2023,36(1):e3000
In this work, binding interactions of artemisinin (ART) and dihydroartemisinin (DHA) with human serum albumin (HSA) and bovine serum albumin (BSA) were investigated thoroughly to illustrate the conformational variation of serum albumin. Experimental results indicated that ART and DHA bound strongly with the site I of serum albumins via hydrogen bond (H-bond) and van der Waals force and subsequently statically quenched the intrinsic fluorescence of serum albumins through concentration-dependent manner. The quenching abilities of two drugs on the intrinsic fluorescence of HSA were much higher than the quenching abilities of two drugs on the intrinsic fluorescence of BSA. Both ART and DHA, especially DHA, caused the conformational variation of serum albumins and reduced the α-helix structure content of serum albumins. DHA with hydrophilic hydroxyl group bound with HSA more strongly, suggesting the important roles of the chemical polarity and the hydrophilicity during the binding interactions of two drugs with serum albumins. These results reveal the molecular understanding of binding interactions between ART derivatives and serum albumins, providing vital information for the future application of ART derivatives in biological and clinical areas. 相似文献
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As one of the basic theories of biodiversity conservation, island biogeography has been widely accepted in the past
decades. Originally, island biogeography was put forward and applied in oceanic environments. But later on, it
was found out that the application was not only limited to oceanic islands, but also in terrestrial environments
with relatively isolated conditions. In terms of biodiversity level, island biogeography generally focuses on a small
scale, such as species diversity and genetic diversity. The studies of biodiversity on a large-scale based on island
biogeography, such as ecosystem and landscape scales, were seldomly conducted. Taking Poyang Lake, the largest
fresh water lake in China as case study area, 30 grasslands were randomly selected to study whether island biogeography can be applied to grasslands at a landscape level from three island attributes (area, distance and shape),
and the most important ecological variable (flooding) in Poyang Lake. The results showed that in general, grasslands have the property of an island, and follow the basic principle of island biogeography. We found the area and
flooding duration were the two most important determinants of landscape diversity. There was a significant positive correlation between the grassland area and the landscape diversity, which could be well expressed by logarithmic function model (R2 = 0.73). There was a negative correlation between flooding duration and landscape
diversity, which could be described by an inverse model (R2 = 0.206). The distance to mainland and the shape
of grassland were correlated with landscape diversity, but the fitting result of the models was not as good as
expected. The possible reason could be that Poyang Lake is a seasonal lake, the water level varies with hydrological
conditions, so that the grasslands are not strongly isolated and their shape is not stable enough required by island
biogeography. Furthermore, it indicates that besides area, distance and shape attributes, flooding strongly affects
the biodiversity of grassland vegetation, and should not be ignored when applying island biogeography theory to
Poyang Lake. This study is expected to be a supplement for island biogeography in terrestrial environments, and
the results are expected to benefit for the biodiversity conservation in Poyang Lake. 相似文献
87.
Xia Jun Hao Xianzhe Wang Tangang Li Huiqin Shi Xiaojuan Liu Yongchang Luo Honghai 《Journal of Plant Growth Regulation》2023,42(1):319-334
Journal of Plant Growth Regulation - Exogenous substances play an important role in the response of cotton to low-temperature conditions during the germination stage, but little is known about the... 相似文献
88.
本研究旨在探究非洲猪瘟病毒(African swine fever virus, ASFV) I226R蛋白(I226R protein, pI226R)抑制cGAS-STING信号通路的作用机制。利用双荧光素酶报告系统和实时荧光定量PCR (real-time quantitative PCR, qPCR)证明pI226R显著抑制cGAS-STING通路介导的I型干扰素及干扰素刺激相关基因的产生。免疫共沉淀及激光共聚焦显微镜试验发现pI226R与cGAS蛋白相互作用。免疫印迹分析证明pI226R通过自噬-溶酶体途径促进cGAS蛋白的降解。同时,pI226R阻碍了cGAS与E3泛素连接酶三基序蛋白56 (tripartite motif protein 56, TRIM56)的结合,导致cGAS的单泛素化减弱,从而抑制了cGAS的活化和cGAS-STING通路的激活。总之,本研究证明ASFV pI226R通过拮抗cGAS进而抑制宿主的抗病毒天然免疫反应,进一步增加了对研究ASFV免疫逃逸机制的理解,为疫苗的研发提供了理论基础。 相似文献
89.
谷子不育系及其相应可育系小孢子发育的细胞学观察 总被引:1,自引:0,他引:1
以谷子2个品种的不育系及其保持系为材料,对其小孢子发育的细胞形态学进行了观察研究。结果表明:昭盟A花药的外部形态及花粉母细胞的发育过程与昭盟B相似,能形成外观正常的三核花粉,但其花药不能开裂散粉。石炮A表现出了败育时间和方式的多样性,且不育系与保持系间在花药长度上有显著差异。此外,两种不育系的维管束都表现出不同程度的发育不良。不良程度与药囊退化程度相关。 相似文献
90.
Wentao Sun Li Luo Jiazi Luo Xixi Song Demin Tang Zishuo Song Meishan Li Hengshan Wang 《化学与生物多样性》2023,20(7):e202300387
Three new compounds ( 1 – 2 , 14 ), as well as 22 known compounds ( 3 – 13 , 15 – 25 ), were extracted for the first time from the Selaginella effusa Alston (S. effusa). For the unknown compounds, the planar configurations were determined via NMR and by high-resolution mass spectrometry, while their absolute configurations were determined by calculated electronic circular dichroism (ECD), and the configuration of the stereogenic center of biflavones 4 – 5 were established for the first time. The pure compounds ( 1 – 25 ) were tested in vitro to determine the inhibitory activity of the enzyme-catalyzed reactions. Compounds 1 – 9 inhibited α-glucosidase with IC50 values ranging from 0.30±0.02 to 4.65±0.04 μM and kinetic analysis of enzyme inhibition indicated that biflavones 1 – 3 were mixed-type α-glucosidase inhibitors. Compounds 12 – 13 showed excellent inhibitory activity against urease, with compound 12 (IC50=4.38±0.31 μM) showing better inhibitory activity than the positive control drug AHA (IC5013.52±0.61 μM). In addition, molecular docking techniques were used to simulate inhibitor-enzyme binding and to estimate the binding posture of the α-glucosidase and urease catalytic sites. 相似文献