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以国家林业局审定的宁夏枸杞新品种‘中科绿川1号’为实验材料,研究不同月份采集的枸杞叶片芦丁含量,以及果实总黄酮、总多糖、总类胡萝卜素、玉米黄素双棕榈酸酯的含量变化。结果显示,叶片芦丁含量在枸杞盛果期较低,抽条期较高;果实总黄酮、总类胡萝卜素、玉米黄素双棕榈酸酯的含量在头茬果中含量较高,盛果期果实含量较低;果实总多糖可能与果实量呈负相关;褐化果(俗称"油果")总黄酮含量与正常果差异不大,可用作提取枸杞黄酮类物质的原材料。研究结果可为枸杞果实分级、成分提取提供新思路。 相似文献
94.
Yan Ding Hua Yang Jing Bo Feng Ying Qiu Dong Sheng Li Yi Zeng 《In vitro cellular & developmental biology. Animal》2013,49(10):771-777
Human umbilical cord-derived mesenchymal stem cells (hUC-MSCs) hold great potential for their therapeutic use in various clinical diseases. Many publications have reported on human blood-derived alternatives to animal serum for culturing mesenchymal stem cells, such as human serum, allogenic umbilical cord blood serum, and human platelet derivatives. However, it is not clear whether human umbilical cord blood plasma (UCBP), as the surplusage of umbilical cord blood mesenchymal stem cell extraction, could be used. In this study, in order to make the best of umbilical cord blood, the human UCBP was dialyzed to replace fetal bovine serum (FBS) in the culture medium. hUC-MSCs were cultured in the new medium. Cell growth rate, specific biomarkers, and differentiation properties were detected to characterize the cell proliferation and MSC-specific properties. The hUC-MSCs cultured in such derived medium were verified with proliferation rate, cluster differentiation markers, cell cycle, as well as differentiation capabilities. Such dialyzed human UCBP is fully comparable with, if not superior to, FBS in deriving and culturing hUC-MSCs. 相似文献
95.
Min Wu Qi Shen Yong Yang Sheng Zhang Wen Qu Jing Chen Hongying Sun Shuqing Chen 《Journal of industrial microbiology & biotechnology》2013,40(6):589-599
Human serum albumin (HSA) and human parathyroid hormone (1-34) [PTH (1-34)] fusion protein [HSA/PTH (1-34)] is a promising long-acting form of PTH (1-34) for osteoporosis treatment. Secretory expression of intact HSA/PTH (1-34) in Pichia pastoris GS115 was accompanied by two degradation fragments, with molecular weights around 66 kDa, in addition to the well-known ~45 kDa HSA-truncated fragment, resulting in a low yield of intact protein. In this study, two internal cleavage sites were identified in the PTH (1-34) portion of the fusion protein by Western Blot analysis. To minimize proteolytic cleavages, several protease genes including PEP4 (encoding proteinase A), PRB1 (proteinase B) and seven YPSs genes (yapsin family members) were knocked out respectively by disruption of the individual genes and the selective combinations. Reduced degradation was observed by single disruption of either PEP4 gene or YPS1 gene, and the lowest level of degradation was observed in a pep4△yps1△ double disruptant. After 72 h of induction, more than 80 % of the HSA/PTH (1-34) secreted by the pep4△yps1△ double disruptant remained intact, in comparison to only 30 % with the wild-type strain. 相似文献
96.
小鼠白蛋白是肝组织特异性表达的蛋白 ,这种特异性是由白蛋白启动子所介导的 .以2 2 35A- 1质粒为模板 ,通过 PCR扩增获得小鼠白蛋白启动子 /增强子基因片段 ,用小鼠白蛋白启动子 /增强子基因片段取代 p HCV- neo4质粒 (含 HCV5′NCR调控荧光素酶基因 )的 CMV启动子 ,构建了一种白蛋白启动子启动转录的 HCV5′NCR调控荧光素酶表达质粒 (p A1 b- HCV) .该质粒能在小鼠肝癌细胞中表达且较小鼠其它癌细胞中表达水平明显增高 ,表明成功地构建了肝特异性表达的 HCV5′NCR调控荧光素酶表达质粒 .该研究为建立肝特异性表达的 HCV5′NCR转基因小鼠模型奠定了基础 ,对评价 HCV特异性反义药物及肝靶向性运载系统的作用具有重要的实际意义 相似文献
97.
Jiayuan Sheng Lei Huang Xiangcheng Zhu Jin Cai Zhinan Xu 《Applied microbiology and biotechnology》2014,98(4):1785-1794
Bacterial peptidoglycan is the cell wall component responsible for various biological activities. Its cytoplasmic precursor UDP-N-acetylmuramyl pentapeptide is biosynthesized by the first six enzymes of peptidoglycan synthetic pathways (Mur enzymes), which are all proved to be important targets for antibiotic screening. In our present work, the genes encoding Mur enzymes from Escherichia coli were co-expressed in the cell-free protein synthesis (CFPS) system, and the activities of Mur enzymes derived from CFPS system were validated by the synthesis of the final product UDP-N-acetylmuramyl pentapeptide. Then this in vitro reconstituted Mur biosynthetic pathway was used to screen a panel of specific antisense oligonucleotides for MurA and MurB. The selected oligonucleotides were proved to eliminate the expression of Mur enzymes, and thus inhibit the Mur biosynthetic pathway. The present work not only developed a rapid method to reconstruct and regulate a biosynthetic pathway in vitro, but also may provide insight into the development of novel antibiotics targeting on peptidoglycan biosynthetic pathway. 相似文献
98.
大黄鱼肌肉生长抑制素基因微卫星序列多态性分析 总被引:3,自引:0,他引:3
肌肉生长抑制素(myostatin,MSTN)参与肌肉生长和脂肪发生的调节.本研究在克隆大黄鱼MSTN cDNA的基础上,对3′端非编码区微卫星序列的多态性及其与体长、体重和肌肉脂肪含量的关系进行了分析.结果表明,获得的cDNA长1 886 bp,在3′端非编码区存在微卫星序列(CA)n.在受检的52个个体中,微卫星序列长度在64~126 bp之间.大部分个体的微卫星序列内存在碱基替换,最常见的碱基替换形式是C→T,属于非完美型微卫星序列.根据该位点微卫星序列长度,在实验群体中共检测到23个等位基因,其中频率为0.019 2的等位基因11个,0.038 5的5个, 0.076 9的3个,0.057 7的2个,0.115 4和0.134 6的各1个.该基因位点的群体杂合度为0.932 7,多态信息含量为0.928 8.微卫星序列长度与大黄鱼体长、体重和肌肉脂肪含量之间的相关系数分别为0.409、0.435和-0.026,P值分别为0.021、0.016和0.878.碱基替换对大黄鱼生长及肌肉脂肪含量均无显著影响. 相似文献
99.
γ-内酰胺酶属于酰胺酶,其中的(+)γ-内酰胺酶能够高效率的动力学拆分外消旋体γ-内酰胺,获得光学纯的(-)γ-内酰胺。光学纯的(-)γ-内酰胺是制备抗病毒药物碳环核苷化合物的重要手性中间体。目前报道共有7个来源于微生物的γ-内酰胺酶,其中来源于Aureoacterium sp.的(-)γ-内酰胺酶的晶体结构获得了解析。根据晶体结构推测的(-)γ-内酰胺酶的催化机理与α/β水解酶超家族的催化机理是类似的。但是,目前还没有(+)γ-内酰胺酶的晶体结构模型的数据及机理的描述。γ-内酰胺酶的研究方向主要包括γ-内酰胺酶的蛋白质工程改造,对不同对映体选择性的γ-内酰胺酶的催化机理的阐述,以及γ-内酰胺酶在生物体内的功能研究。 相似文献
100.
Li Han Xuan Zhou Yiting Zhao Shusheng Zhu Lixia Wu Yunlu He Xiangrui Ping Xinqi Lu Wuying Huang Jie Qian Lina Zhang Xi Jiang Dan Zhu Chongyu Luo Saijie Li Qian Dong Qijing Fu Kaiyuan Deng Xin Wang Lei Wang Sheng Peng Jinsong Wu Weimin Li Jií Friml Youyong Zhu Xiahong He Yunlong Du 《植物学报(英文版)》2020,62(9):1433-1451
Endophytic fungi can be beneficial to plant growth. However, the molecular mechanisms underlying colonization of Acremonium spp. remain unclear.In this study, a novel endophytic Acremonium strain was isolated from the buds of Panax notoginseng and named Acremonium sp. D212. The Acremonium sp. D212 could colonize the roots of P. notoginseng,enhance the resistance of P. notoginseng to root rot disease, and promote root growth and saponin biosynthesis in P. notoginseng. Acremonium sp. D212 could secrete indole-3-acetic acid(IAA) and jasmonic acid(JA), and inoculation with the fungus increased the endogenous levels of IAA and JA in P. notoginseng. Colonization of the Acremonium sp. D212 in the roots of the rice line Nipponbare was dependent on the concentration of methyl jasmonate(Me JA)(2–15 μmol/L) and 1-naphthalenacetic acid(NAA)(10–20 μmol/L). Moreover, the roots of the JA signaling-defective coi1-18 mutant were colonized by Acremonium sp. D212 to a lesser degree than those of the wild-type Nipponbare and mi R393 boverexpressing lines, and the colonization was rescued by Me JA but not by NAA. It suggests that the cross-talk between JA signaling and the auxin biosynthetic pathway plays a crucial role in the colonization of Acremonium sp. D212 in host plants. 相似文献