全柱成像毛细管等电聚焦电泳测定艾塞那肽等电点

目的:采用新一代全柱成像毛细管等电聚焦电泳技术(CIEF-WCID)测定艾塞那肽等电点。方法:采用互补性金属氧化物半导体成像技术对样品等电聚焦过程进行实时记录,根据适宜的marker计算得到艾塞那肽的等电点,并对方法的准确度与重复性进行考察。结果:测得艾塞那肽等电点为5.46,与凝胶电泳结果基本一致,相对标准偏差为0.11%。CIEF-WCID方法快速准确,相对误差小于2.5%,重复性良好。结论:CIEF-WCID作为一种新的技术手段可用于艾塞那肽等电点的分析,方法快速、准确、重复性好,可为多肽的质量控制提供一种可靠的分析方法。     

牛凝血酶等电点的初步测定

作为一种新型的速效局部止血药和工具酶,凝血酶在临床和生物学研究中的应用十分广泛,牛血浆是其重要的来源之一。等电点沉淀是提取牛凝血酶首要和关键的步骤,测定其等电点后,再用此法时将得到更纯的凝血酶粗制品。本实验的目的是采用载体两性电解质pH梯度等电聚焦电泳的方法,结合SDS-PAGE测定牛凝血酶的等电点。经双向电泳后,SDS聚丙烯酰胺凝胶中出现了4个清晰的斑点,分别测定它们的分子量和等电点, 其中一个斑点与牛凝血酶B链的分子量一致为32kDa,其等电点为5．19．     

等电聚焦法测定2.5S NGF的等电点

采用水平等电聚焦法测定了２５Ｓｍ神经生长因子（ＮＧＦ）的等电点。经测定,纯化的２５ＳｍＮＧＦ的等电聚焦为三条带,这与文献报道相一致,等电点ｐＨ值分别为ｐＨ８７、９０、９３,其主要成分为β亚基ＮＧＦ及其修饰物的混合物,包括在羧基端失去８个氨基酸残基和在氨基端失去１个精氨酸残基,由这三种组分构成的ＮＧＦ统称为２５ＳｍＮＧＦ。     

单克隆抗体的等电聚焦

本文采用聚丙烯酰胺凝胶等电聚焦和Phast-system仪等电聚焦测定12份HBsAg McAb IgG的等电点,并对两种方法测定的误差和优缺点进行了讨论。     

TD—PAGE中若干技术的改进

本文介绍了ＴＤＰＡＧＥ实验操作中一些技术的改进,为得到较好的电泳效果提供了简单可行的方法。     

TD-PAGE中若干技术的改进

本文介绍了TD-PAGE 实验操作中一些技术的改进,为得到较好的电泳效果提供了简单可行的方法。     

蓝马鸡,褐马鸡及其杂种蛋白质聚焦电泳观察

本文比较了在笼养情况下,蓝马鸡、褐马鸡及杂种的形态和红细胞内的血红蛋白（Ｈｂ）、乳酸脱氢酶和苹果酸脱氢酶（ＬＤＨ和ＭＤＨ）,血浆中的淀粉酶和酯酶（Ａｍｙ和Ｅｓ）的聚焦电泳图谱。结果指出ＬＤＨ、ＭＤＨ和Ｅｓ同工酶在三种鸟之间差别不明显;而Ｈｂ和Ａｍｙ表现出较显著的差异;杂种不管在电泳图谱方面,还是在形态方面都介于蓝马鸡和揭马鸡之间。     

新的水稻谷蛋白α—1亚基缺失突变体

从水稻受精卵MNU处理后代中获得4个谷蛋白α－1亚基缺失突变品系。SDS－PAGE和IEF分析表明这些突变体在共同缺失1条pI6.82多肽的同时,或形成新的多肽,或其他多肽表现量增加,这些突变体是由结构基因控制的,IEF分析同时显示2条多肽pI6.82和pI8.58源自同一条谷蛋白前驱体。这4个突变体对于改良水稻谷蛋白品质、研究谷蛋白生物合成遗传调控机制以及揭示谷蛋白基因功能是不可多得的研究材料。     

三种分析水稻F1代幼苗生长过程中酯酶同工酶变化的电泳方法比较

利用聚酯胶片作为凝胶支持物的超薄等电聚焦电泳(UTLIEF)研究水稻F1种子萌发过程中的酯酶同工酶多态性变化的结果表明,UTLIEF相比非变性不连续聚丙烯酰胺电泳(native-PAGE)和常规等电聚焦电泳(IEF)得到的酯酶同工酶图谱更清晰,酶带数目和强弱的多态性变化更高,用pH 2～9的两性电解质时等电聚焦的电泳效果较好.     

利用等电聚焦电泳研究黄单胞菌分类

对黄单胞菌的4个种及29个致病变种的代表菌株进行了等电聚焦电泳研究,发现所测定的黄单胞菌种间、致病变种间蛋白质图谱差别很大。电泳结果经聚类分析表明,某些致病变种间的差别并不一定比种间的差别小,说明某些致病变种可以上升到种这一分类地位。引起细菌性黑颖病的黄单胞菌禾谷致病变种、小麦致病变种、大麦致病变种间差别很小,仅有6条蛋白质谱带的差别。因此这3个致病变种的分类地位需重新考虑,同时说明等电聚焦电泳对黄单胞菌种下分类具有一定指导意义。     

小麦高分子量麦谷蛋白亚基等电点的特性分析

运用IEF×SDS-PAGE和NEPEGE×PAGE 2种双向电泳技术对5个普通小麦品种和1个硬粒小麦品种的高分子量麦谷蛋白亚基等电点的特性进行了研究。结果表明,等位亚基之间的等电点比较相近,而非等位亚基之间的等电点存在不同程度的差异,其中普通小麦G lu-B 1位点的亚基等电点最高,属于碱性类型。用NEPHGE×SDS-PAGE电泳能够对G lu-B 1亚基的等电点特性进行比较分析。通过对麦谷蛋白亚基等电点特性及变异规律进行分析,可以为精确判断亚基类型和鉴定遗传新种质等研究工作提供有价值的信息。     

Paracrine Interactions within the Pancreatic Islet Determine the Glycemic Set Point

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Isoelectric subtyping of the PGM1 in the Icelandic population

Phenotypes for the red blood cell enzyme phosphoglucomutase (PGM1) were determined by isoelectric focusing for a population of 2,501 Icelandic individuals. All ten phenotypes were observed, and the frequencies of four alleles at the PGM1 locus were as follows: PGM1 1+=0.6875; PGM1 1−=0.1124; PGM1 2+=0.1419, and PGM1 2−=0.0582. These results have been compared with those found in other northern European populations.     

Isoelectric Point Based Dual Sensitive Peptide-Drug Conjugate Prodrug to Target Solid Tumors

International Journal of Peptide Research and Therapeutics - Anticancer drugs (Doxorubicin, Methotrexate, Daunorubicin, etc.,) shows excellent activity on killing cancer cells, equal amount of...     

A Method to Determine the end Point of Decalcification of Hard Tissue and Bone

A method for decalcification end point determination of mineralized tissue is described. The calcium content of the decalcification solution was determined colorimetrically with a “continuous automatic analyzer” with a high degree of accuracy. The end point method used has been tested on two decalcification methods, 5% nitric acid with or without ultrasonic treatment. The results suggest it is possible to quantitate the decalcification process.     

The Effect of the Chemical Nature of a Decolorizer on Its Functioning. II. the Apparent Isoelectric Point

The isoelectric point of a bacterial system is the hydrogen-ion concentration at which there is equal retention of anion and cation. Defining this point as that at which there is equal retention of acidic and basic stain when acetone is used as a decolorizer, it is shown that acidic decolorizers shift the experimentally determined point to a higher pH-value while basic decolorizers shift it to a lower value. Thus basic decolorizers show abnormally high decolorizing power toward smears stained with acid dyes, and acid decolorizers show the same abnormal behavior toward smears stained with basic dye. By basic decolorizer is meant, not one of high pH-value, but one which will form a salt with acids, as for example pyridin or anilin. This indicates an ionic chemical equilibrium as a factor in the mechanism of staining.     

Delineating the Specific Influence of Virus Isoelectric Point and Size on Virus Adsorption and Transport through Sandy Soils

Many of the factors controlling viral transport and survival within the subsurface are still poorly understood. In order to identify the precise influence of viral isoelectric point on viral adsorption onto aquifer sediment material, we employed five different spherical bacteriophages (MS2, PRD1, Qβ, X174, and PM2) having differing isoelectric points (pI 3.9, 4.2, 5.3, 6.6, and 7.3 respectively) in laboratory viral transport studies. We employed conventional batch flowthrough columns, as well as a novel continuously recirculating column, in these studies. In a 0.78-m batch flowthrough column, the smaller phages (MS2, X174, and Qβ), which had similar diameters, exhibited maximum effluent concentration/initial concentration values that correlated exactly with their isoelectric points. In the continuously recirculating column, viral adsorption was negatively correlated with the isoelectric points of the viruses. A model of virus migration in the soil columns was created by using a one-dimensional transport model in which kinetic sorption was used. The data suggest that the isoelectric point of a virus is the predetermining factor controlling viral adsorption within aquifers. The data also suggest that when virus particles are more than 60 nm in diameter, viral dimensions become the overriding factor.