| In vivo and in vitro 31P-NMR Study of the Phosphate Transport and Polyphosphate Metabolism in Hebeloma cylindrosporum in Response to Plant Roots Signals
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Author:
Date:
2018-08-20
[Abstract] We used in vivo and in vitro phosphorus-31 nuclear magnetic resonance (31P-NMR) spectroscopy to follow the change in transport, compartmentation and metabolism of phosphate in the ectomycorrhizal fungus Hebeloma cylindrosporum in response to root signals originating from host (Pinus pinaster) or non-host (Zea mays) plants. A device was developed for the in vivo studies allowing the circulation of a continuously oxygenated mineral solution in an NMR tube containing the mycelia. The in vitro studies were performed on ...
[摘要] 我们使用体内和体外磷-31核磁共振（ 31 P-NMR）光谱来跟踪运输，分区和 外生菌根真菌 Hebeloma cylindrosporum 中的磷酸盐代谢响应来自宿主（ Pinus pinaster ）或非宿主（ Zea mays ）的根信号植物。 开发了一种用于体内研究的装置，其允许连续氧化的矿物质溶液在含有菌丝体的NMR管中循环。 在几个连续的处理步骤（在液氮中冷冻;用高氯酸压碎;消除高氯酸;冷冻干燥;在适当的液体培养基中溶解）后，对真菌材料进行体外研究。
【背景】 菌根真菌和植物之间的关联改善了宿主植物的P营养（Smith和Read，2008; Plassard和Dell，2010; Cairney，2011; Smith 等人，，2015）。这种积极效应主要归因于真菌菌丝对磷酸盐（Pi）的吸收，探测了在活跃吸收根周围的耗竭区以外的大量土壤（Smith和Read，2008; Cairney，2011; Smith et al。< em="">，2015）和真菌细胞分泌细胞外磷酸酶（Quiquampoix和Mousain，2005）。吸收的Pi部分地掺入磷酸化的代谢物，磷脂和核酸中，并且部分地浓缩成多磷酸盐（PolyP），其中它们构成液泡中的储存池（Ashford 等人，，1994）。该协议详述了一种装置，该装置允许通过 31 ...
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| Analysis of Total Se Content in Rice
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Author:
Date:
2014-10-05
[Abstract] Total Se content in rice is normally low and it is difficult to determine it exactly because of Se volatilization and pollution during the digestion process. In this method, rice sample is digested thoroughly and Se volatilization is reduced greatly by designing a specific digestion tube, increasing digestion temperature by three steps, controlling the amount of mixed acid and adjusting the location of digestion tube in the digestion furnace. Se pollution is also reduced greatly by specific cleaning treatments.
[摘要] 水稻总硒含量通常较低，很难准确地确定它是由于在蒸煮过程中的Se挥发和污染。 在该方法中，通过设计特定的消化管，提高消化温度三个步骤，控制混合酸的量和调节消化管在消化炉中的位置，大大消化大米样品并且大大减少Se的挥发。 由于特定的清洁处理，Se污染也大大减少
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| Assays for Determination of Acetylesterase Activity and Specificity Using pNP-acetyl and Acetylated Polysaccharides as Substrates
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Author:
Date:
2014-02-05
[Abstract] The acetylesterases are hydrolytic enzymes which in plants cleave acetyl groups from acetylated cell wall components, primarily polysaccharides. To estimate acetylesterase activity in plant apoplast, two assays can be used. First assay is a direct measurement of the acetylesterase activity in protein extract using synthetic substrate, pNP-acetyl. In this assay, amount of pNP released after hydrolysis of pNP-acetyl is determined by measuring the intensity of developed yellow color using spectrophotometer. The absorbance of reaction mixture is directly proportional to the activity of ...
[摘要] 乙酰酯酶是水解酶，其在植物中从乙酰化的细胞壁组分，主要是多糖中切割乙酰基。为了估计植物质外体中的乙酰酯酶活性，可以使用两种测定。第一个测定是使用合成底物，pNP-乙酰基直接测量蛋白质提取物中的乙酰酯酶活性。在该测定中，通过使用分光光度计测量显色黄色的强度来确定pNP-乙酰基水解后释放的pNP的量。反应混合物的吸光度与反应混合物中乙酰酯酶的活性成正比。第二个测定是乙酰酯酶活性及其对天然多糖的特异性的测定，并且基于高氯酸铁和乙酰基残基之间的相互作用，导致可以使用分光光度计定量的乙酰氧肟酸络合物。在该测定中，使用高粱酸铁试剂来估计与质外体提取物孵育的市售乙酰化多糖（来自Birchwood的木聚糖用于乙酰木聚糖酯酶的果胶;来自柑橘属水果的用于鼠李半乳糖醛酸聚糖乙酰酯酶的果胶;或任何其他可用的目的多糖）和量的从该多糖中释放的乙酰基残基，试剂（方案由McComb和McCready，1957修改）。产生的有色复合物的吸光度与从乙酰化多糖释放的乙酰基的量成正比。
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