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71.
本文报导金发草属Pogonatherum Beauv.中1新种,即二芒金发草P.biaristatum S.L.Chen et G.Y.Sheng及觿茅属Dimeria R.Br.中2新种,即异花觿茅D.heterantha S.L.Chen et G.Y.Sheng及广西觿茅D.guangxiensis S.L.Chen et G.Y.Sheng.  相似文献   
72.
拟南芥APETALA1(AP1)既是一个花分生组织特征基因又是一个花器官特征基因,在花器官发育中控制花萼和花瓣的发育。通过GUS染色进一步证实AP1主要在茎尖、花萼、花瓣和花托的位置表达。启动子分析发现,AP1启动子区包含了包括W-box在内的大量顺式作用元件,暗示相关转录调控因子参与了对AP1的调控。21个WRKY基因单突变后并不改变AP1在花中的表达,但是AP1突变则增强了检测的10个WRKY基因中7个WRKY基因的表达,暗示AP1参与了对WRKY基因的基础表达的调控。这个结果也暗示AP1可能通过控制花萼和花瓣的发育从而参与了对花的基础抗性。  相似文献   
73.
With the development of functional genomics research, large-scale proteomics studies are now widespread, presenting significant challenges for data storage, exchange, and analysis. Here we present the Integrated Proteomics Exploring Database (IPED) as a platform for managing proteomics experimental data (both process and result data). IPED is based on the schema of the Proteome Experimental Data Repository (PEDRo), and complies with the General Proteomics Standard (GPS) drafted by the Proteomics Standards Committee of the Human Proteome Organization. In our work, we developed three components for the IPED platform: the IPED client editor, IPED server software, and IPED web interface. The client editor collects experimental data and generates an extensible markup language (XML) data file compliant with PEDRo and GPS; the server software parses the XML data file and loads information into a core database; and the web interface displays experimental results, to provide a convenient graphic representation of data. Given software convenience and data abundance, IPED is a powerful platform for data exchange and presents an important resource for the proteomics community. In its current release, IPED is available at http://www. biosino.org/iped2.  相似文献   
74.
The baculovirus–insect expression system is a popular tool for recombinant protein production. The standard method for infecting insect larvae with recombinant baculovirus for protein production involves either feeding occlusion bodies or injecting budded virus into the cuticle. In this study, we showed that the recombinant Autographa californica multiple nucleopolyhedrovirus (AcMNPV) at titers >108 pfu/mL efficiently infected Trichoplusia ni (T. ni) larvae through aerosol inoculation of budded virus at a pressure of 5.5 × 104 Pa. The dipping T. ni larvae in virus‐containing solution efficiently infected them. These results indicate that surface contamination, either by aerosol or dipping, lead to infection via spiracles. The aerosol infection route for AcMNPV was restricted to T. ni and Plutella xylostella larvae, whereas Spodoptera litura and Helicoverpa armigera larvae were resistant to this inoculation process. The yields of the reporter proteins DsRed and EGFP from T. ni larvae following aerosol infection were nearly identical to those following oral feeding or injection. This alternative baculovirus infection strategy facilitates recombinant protein and virus production by insect larvae. © 2009 American Institute of Chemical Engineers Biotechnol. Prog., 2009  相似文献   
75.
Realizing energy harvesting from water flow using triboelectric generators (TEGs) based on our daily wearable fabric or textile has practical significance. Challenges remain on methods to fabricate conformable TEGs that can be easily incorporated into waterproof textile, or directly harvest energy from water using hydrophobic textile. Herein, a wearable all‐fabric‐based TEG for water energy harvesting, with additional self‐cleaning and antifouling properties is reported for the first time. Hydrophobic cellulose oleoyl ester nanoparticles (HCOENPs) are prepared from microcrystalline cellulose, as a low‐cost and nontoxic coating material to achieve superhydrophobic coating on fabrics, including cotton, silk, flax, polyethylene terephthalate (PET), polyamide (nylon), and polyurethane. The resultant PET fabric‐based water‐TEG can generate an instantaneous output power density of 0.14 W m?2 at a load resistance of 100 MΩ. An all‐fabric‐based dual‐mode TEG is further realized to harvest both the electrostatic energy and mechanical energy of water, achieving the maximum instantaneous output power density of 0.30 W m?2. The HCOENPs‐coated fabric provides excellent breathability, washability, and environmentally friendly fabric‐based TEGs, making it a promising wearable self‐powered system.  相似文献   
76.
酚类物质对杉木幼苗15N养分吸收、分配的影响   总被引:16,自引:0,他引:16       下载免费PDF全文
 应用15N同位素示踪技术,通过盆栽实验研究了香草醛和对羟基苯甲酸对杉木(Cunninghamia lanceolata)幼苗N素养分吸收、分配的影响,结果发现香草醛及其与对羟基苯甲酸的混合物(浓度比1∶1)明显抑制了杉木幼苗的生长和对15NO3-离子的吸收,10 mmol·L-1的香草醛使杉木幼苗根、茎、叶生物量分别下降了25.3%、13.5%、5.7%,15N吸收量分别减少了38.5%、48.1%、46.5%;10 mmol·L-1的混合物使杉木幼苗根、茎、叶生物量分别下降了33.5%、36.0%、21  相似文献   
77.
去甲斑蝥素是我国自行研制的抗肿瘤药物,在临床上主要用于消化道肿瘤的治疗.实验表明,去甲斑蝥素可引起人胃癌BGC-823细胞发生 M期阻滞及细胞凋亡.进一步利用双向电泳和质谱技术,筛选出了去甲斑蝥素抑癌作用相关蛋白.研究显示,线粒体热休克蛋白CH60、线粒体ATP合酶d亚单位、内质网葡萄糖调节蛋白GRP78、线粒体Hsp70的辅助因子GRPE1、SH3L3以及染色质组装因子1小亚基RBBP4参与了去甲斑蝥素的抑癌作用.研究提示,去甲斑蝥素可能通过促进线粒体热休克蛋白及p53的表达进而激活caspase-3依赖的凋亡通路,并且去甲斑蝥素在引发内质网协迫之后,可通过抑制胞外信号调节激酶(extracellular signal regulated kinase, ERK)的活性促进肿瘤细胞的凋亡.进一步分析了去甲斑蝥素与线粒体ATP合酶抑制剂寡霉素A的联合用药对人胃癌细胞生长的影响,结果表明,联合用药的抑瘤效果比单独用药的抑瘤效果显著,提示去甲斑蝥素可能通过抑制线粒体ATP合酶功能抑制BGC-823生长.上述结果为优化去甲斑蝥素的联合用药方案提供了新线索.  相似文献   
78.
The epithelial sodium channel (ENaC) is composed of three homologous subunits termed alpha, beta, and gamma. Previous studies suggest that selected residues within a hydrophobic region immediately preceding the second membrane-spanning domain of each subunit contribute to the conducting pore of ENaC. We probed the pore of mouse ENaC by systematically mutating all 24 amino acids within this putative pore region of the alpha-subunit to cysteine and co-expressing these mutants with wild type beta- and gamma-subunits of mouse ENaC in Xenopus laevis oocytes. Functional characteristics of these mutants were examined by two-electrode voltage clamp and single channel recording techniques. Two distinct domains were identified based on the functional changes associated with point mutations. An amino-terminal domain (alpha-Val(569)-alpha-Gly(579)) showed minimal changes in cation selectivity or amiloride sensitivity following cysteine substitution. In contrast, cysteine substitutions within the carboxyl-terminal domain (alpha-Ser(580)-alpha-Ser(592)) resulted in significant changes in cation selectivity and moderately altered amiloride sensitivity. The mutant channels containing alphaG587C or alphaS589C were permeable to K(+), and mutation of a GSS tract (positions alpha587-alpha589) to GYG resulted in a moderately K(+)-selective channel. Our results suggest that the C-terminal portion of the pore region within the alpha-subunit contributes to the selectivity filter of ENaC.  相似文献   
79.
果胶甲酯酶的结构与功能研究进展   总被引:1,自引:0,他引:1  
王胜  孟昆  罗会颖  姚斌  涂涛 《生物工程学报》2020,36(6):1021-1030
果胶甲酯酶(PME)是一种重要的果胶酶,其水解果胶中的甲酯基从而释放甲醇并降低果胶的甲酯化程度。目前在食品加工、茶饮料、造纸等生产工艺中有着广泛的应用前景。随着对PME的深入研究,已报道了几种不同来源的酶晶体结构,对这些已获得的晶体结构进行分析发现,PME属于右手平行β-螺旋结构,其催化残基为2个保守的天冬氨酸和1个谷氨酰胺残基,并且在催化过程中分别起到了一般酸碱、亲核试剂以及稳定中间体的作用。同时对其底物特异性进行分析,初步了解其底物与活性位点的识别机制。文中针对这几个相关方面进行了系统的综述。  相似文献   
80.
Entomopathogenic fungi such as Metarhizium rileyi and Beauveria bassiana are widely used insect biological control agents. Little, however, is known concerning genetic or enzymatic factors that differentiate the mechanisms employed by these two fungal pathogens to infect target hosts. Infection by either of these organisms is known to increase levels of the growth and molting hormone, ecdysone, which also regulates the expression of a number of innate immune pathways. M. rileyi, but not B. bassiana, has apparently evolved an ecdysteroid-22-oxidase (MrE22O) that inactivate ecdysone. We show that deletion of MrE22O impaired virulence compared with the wild-type strain, with an increase in ecdysone titer seen in hosts that was coupled to an increase in the expression of antimicrobial genes. An M. rileyi strain engineered to overexpress MrE22O (MrE22OOE), as well as trans-expression in B. bassiana (Bb::MrE220OE) resulted, in strains displaying enhanced virulence and dampening of host immune responses compared with their respective wild-type parental strains. These results indicate that ecdysone plays an important role in mediating responses to fungal infection and that some insect pathogenic fungi have evolved mechanisms for targeting this hormone as a means for facilitating infection.  相似文献   
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