| In vitro Chaperone Activity Assay Using α-Amylase as Target Protein
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Author:
Date:
2018-06-20
[Abstract] Small heat shock proteins (sHSP) are stress proteins which are ubiquitously found in almost all living organisms. They function as molecular chaperones, which assist in protein folding during translation and in the prevention of irreversible protein aggregation under denaturing conditions. This protocol describes the use of α-amylase as target protein in assessing the chaperone activity of wild and mutant recombinant small heat shock proteins of Mycobacterium leprae. Chaperone activity of these proteins, along with α-crystallin, a standard sHSP was demonstrated using a new method employing their protective effect against heat denaturation of α-amylase from porcine pancreas. The regained enzymatic activity of the α-amylase was demonstrated on starch agar plates stained with ...
[摘要] 小热休克蛋白（sHSP）是在几乎所有生物体中无处不在发现的应激蛋白。 它们作为分子伴侣起作用，这有助于在翻译过程中蛋白质折叠以及在变性条件下预防不可逆的蛋白质聚集。 该协议描述了使用α-淀粉酶作为靶蛋白来评估麻风分枝杆菌的野生和突变重组小热休克蛋白的分子伴侣活性。 这些蛋白质的陪伴分子活性以及标准sHSP的α-晶状体蛋白通过采用其对猪胰α-淀粉酶的热变性的保护作用的新方法被证实。 在用碘 - 碘化钾（I 2 -KI）溶液染色的淀粉琼脂平板上证实α-淀粉酶的重新酶活性。
【背景】热休克蛋白（HSPs）是一组保守的蛋白质，当细胞暴露于外部应激（包括热应激和冷应激）时诱导蛋白质。该组中的大多数成员在功能上与蛋白质折叠和解折叠机制有关。小热休克蛋白（sHSPs）是热休克蛋白的子集，其分子大小为12至43kDa，并且保守的C末端区域称为'α-晶域'。 sHSP通过与部分未折叠的蛋白结合并阻止其完全变性而显示ATP非依赖性分子伴侣活性。有几种用于证明sHSPs的体外伴侣蛋白活性的方法，其使用各种底物蛋白如RuBisCO（Goloubinoff等人，1989），rhodanese（Mendoza等人（Farahbakhsh等，1995），溶菌酶（Rozema和Gellman，1996），苹果酸脱氢酶（Lee等， ...
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| Determination of Intracellular ATP Levels in Mycelium of Fusarium oxysporum
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Author:
Date:
2016-07-20
[Abstract] Glycolysis provides metabolites for energy production via oxidative phosphorylation during vegetative growth of Fusarium oxysporum. Therefore, determination of intracellular ATP levels might be of valuable help to analyze regulation of glycolysis/gluconeogenesis pathways. The protocol described here can be applied to other filamentous fungi.
[摘要] 糖酵解在玉蜀黍的营养生长期间通过氧化磷酸化提供能量产生的代谢物。 因此，细胞内ATP水平的测定可能有助于分析糖酵解/糖异生途径的调节。 这里描述的协议可以应用于其他丝状真菌
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| Separation of Free and Bound cAMP in Mycobacteria
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Author:
Date:
2016-07-20
[Abstract] Mycobacterial genomes encode a plethora of genes that are involved in the synthesis, utilization and degradation of cAMP. The genome of M. tuberculosis H37Rv, for example, encodes 16 adenylyl cyclases and 10 genes harbouring the cyclic nucleotide-binding (CNB) domain (Shenoy and Visweswariah, 2006). Cyclic AMP is efficiently secreted by mycobacteria, and cytosolic as well as extracellular levels of cAMP can reach hundreds of micromolar. We have recently reported that an abundantly expressed universal stress protein (USP; Rv1636 in M. tuberculosis H37Rv and MSMEG_3811 in M. smegmatis, respectively) binds cAMP (Banerjee et al., 2015). Given the number of cAMP-binding proteins present in mycobacteria, it is expected that a significant fraction of ...
[摘要] 分枝杆菌基因组编码涉及cAMP的合成，利用和降解的大量基因。例如，结核分枝杆菌H37Rv的基因组编码16个腺苷酸环化酶和10个携带环核苷酸结合（CNB）结构域的基因（Shenoy和Visweswariah，2006）。循环AMP由分枝杆菌有效分泌，细胞溶质以及细胞外cAMP水平可达数百微摩尔。我们最近报道，大量表达的普遍应激蛋白（USP; Rv1636在结核分枝杆菌H37Rv和MSMEG_3811分别在耻垢分枝杆菌中）分别结合cAMP（Banerjee等，2015）。鉴于存在于分枝杆菌中的cAMP结合蛋白的数量，预期细胞内cAMP的显着部分可能与蛋白质结合。通常用于测量cAMP的方法是放射免疫测定（RIA）和ELISA。然而，这些方法包括将cAMP“结合”解离成蛋白质的样品的预先酸化，因此代表样品中存在的“总”cAMP。在本协议中，我们描述了一种将cAMP'结合'蛋白质与蛋白质“自由”分离或与蛋白质不相关的方法。这通过使细胞溶质级分或培养物上清液通过具有3kDa截止值的膜过滤来进行。只有'自由'cAMP才能通过膜。因此，滤液中的cAMP浓度代表样品中的“游离”cAMP。原始细胞溶质级分或培养上清液中的环AMP水平代表“总”cAMP浓度。从“总”中减去“自由”提供了与蛋白质结合的cAMP量。
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