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991.
Yuxiang Yao Hongzhi Tang Huixue Ren Hao Yu Lijuan Wang Ping Xu 《Journal of bacteriology》2012,194(20):5714-5715
We announce a 4.63-Mb genome assembly of an isolated bacterium that is the first sequenced nicotine-degrading Arthrobacter strain. Nicotine catabolism genes of the nicotine-degrading plasmid pAO1 were predicted, but plasmid function genes were not found. These results will help to better illustrate the molecular mechanism of nicotine degradation by Arthrobacter. 相似文献
992.
城市公园是城市生态系统的重要组成部分和城市生物多样性热点地区,具有丰富的声景观资源。由于声景观及声学方法具有信息量大,成本低,低侵入的特点,因此其研究和应用对生态系统健康及监测具有较高价值。声景观研究通过总结生物声的活动或多样性来衡量生物多样性。记录了北京20个城市公园的春季声景观,使用定量方法描述了声景观特征与变化;测试三种了已被证明与生物多样性相关并被广泛使用的声学指数(BIO、ADI、NDSI)与植被群落关系,完成了城市环境中声景观与环境关系的初步探究。研究结果表明:(1)声学指数能够有效表征城市公园声景观信息,具有显著的时间动态特性,能准确反映鸟类黎明合唱等重要生物生态活动;(2)声学强度指数也具有显著的时间动态变化和沿频率梯度的变化,不同的频率区间反映了不同声学群落的活动信息;(3)植被结构尤其是垂直结构对声景观起着重要作用,垂直异质性越大,声学多样性越高。发现支持声景观作为公园植被状况的度量,强调了其作为生物多样性和生态系统健康状况监测方法,用于城市管理和可持续发展的巨大潜力。 相似文献
993.
M. Ts. Itigilova N. A. Tashlykova E. Yu. Afonina 《Contemporary Problems of Ecology》2016,9(6):783-789
The content and accumulation of particular heavy metals in phyto- and zooplankyon from the technogenically transformed Lake Kenon (Chita, Transbaikalia) have been studied. Algae contains the highest concentrations of Zn and Sr. Zooplankton is characterized by concentrations of Ni, Cu, Cd, and Hg either below or equivalent to those known for other water bodies. It has been shown that the distribution of heavy metals in the studied water body is differentiated. Their greatest concentration has been registered in the plankton of technogenically contaminated sites—CHPP and Oil Tank Farm. 相似文献
994.
J F Riou M Umbhauer D L Shi J C Boucaut 《Biology of the cell / under the auspices of the European Cell Biology Organization》1992,75(1):1-9
Tenascin is a large oligomeric extracellular matrix (ECM) glycoprotein whose expression is highly restricted during vertebrate development. It has a characteristic hexameric quaternary structure with six arms linked to a central globular domain. Each arm contains a single polypeptide with the central globular domain formed by the covalent association of the N-terminal ends of the six polypeptides. Tenascin first appears during development, associated with the neural crest cell migration pathways of mammalian, avian and amphibian embryos. During later development, it is observed at sites of cartilage, bone and tendon formation. Tenascin expression also occurs in defined areas in the developing nervous system and in condensing mesenchyme, in response to epithelio-mesenchymal interactions. The function of tenascin in these different morphogenetic processes is not yet clearly understood. Tenascin can promote neurite outgrowth in vitro and can inhibit cell interactions with fibronectin. Results based on antibody mapping and molecular cloning indicate that these properties involve two distinct cell binding sites. Together with its highly regulated expression in the embryo, these properties suggest that tenascin plays a key role in the control of cell migration and differentiation during development. 相似文献
995.
996.
Russian Journal of Marine Biology - The seasonal accumulation of the amnesic toxin domoic acid (DA) in the tissues of two commercial species of bivalves from Vostok Bay (the Sea of Japan) was... 相似文献
997.
998.
999.
Andriy I. Vovk Lyudmyla A. Kononets Vsevolod Yu. Tanchuk Sergiy O. Cherenok Andriy B. Drapailo Vitaly I. Kalchenko Valery P. Kukhar 《Bioorganic & medicinal chemistry letters》2010,20(2):483-487
Inhibition of Yersinia protein tyrosine phosphatase by calix[4]arene mono-, bis-, and tetrakis(methylenebisphosphonic) acids as well as calix[4]arene and thiacalix[4]arene tetrakis(methylphosphonic) acids have been investigated. The kinetic studies revealed that some compounds in this class are potent competitive inhibitors of Yersinia PTP with inhibition constants in the low micromolar range. The binding modes of macrocyclic phosphonate derivatives in the enzyme active center have been explained using computational docking approach. The results obtained indicate that calix[4]arenes are promising scaffolds for the development of inhibitors of Yersinia PTP. 相似文献
1000.
Baike Wang Ning Li Juan Wang Shaoyong Huang Yaping Tang Shengbao Yang Tao Yang Qiang Wang Qinghui Yu Jie Gao 《Proteomics》2020,20(8)
So far, over 50 spontaneous male sterile mutants of tomato have been described and most of them are categorized as genetic male sterility. To date, the mechanism of tomato genetic male sterility remained unclear. In this study, differential proteomic analysis is performed between genetic male sterile line (2‐517), which carries the male sterility (ms1035) gene, and its wild‐type (VF‐11) using isobaric tags for relative and absolute quantification‐based strategy. A total of 8272 proteins are quantified in the 2–517 and VF‐11 lines at the floral bud and florescence stages. These proteins are involved in different cellular and metabolic processes, which express obvious functional tendencies toward the hydroxylation of the ω‐carbon in fatty acids, the tricarboxylic acid cycle, the glycolytic, and pentose phosphate pathways. Based on the results, a protein network explaining the mechanisms of tomato genetic male sterility is proposed, finding the compromising fat acid metabolism may cause the male sterility. These results are confirmed by parallel reaction monitoring, quantitative Real‐time PCR (qRT‐PCR), and physiological assays. Taken together, these results provide new insights into the metabolic pathway of anther abortion induced by ms1035 and offer useful clues to identify the crucial proteins involved in genetic male sterility in tomato. 相似文献