聚丙烯酰胺凝胶电泳的一种辅助辨型方法

聚丙烯酰胺凝胶电泳（PAGE）是实验室常用的基本鉴定方法之一。但由于做胶方式以及各实验室仪器设备良莠不齐，经过一系列纷繁复杂的操作，电泳结果未必尽如人意。其中凝胶带型的判断就是一个较为困惑的问题，一般的聚丙烯酰胺胶跑出的条带总体上都有弧度，越是靠近凝胶两侧越是严重。在本实验中，我们设计了一种较为简单易行的方案，即将难以区分的条带样品做成混合样marker来辅助辨型，通过调整电压和凝胶浓度来达到区分条带的目的。我们用该方案可以将相差0～3bp大小的条带区分开来。     

Cellulose acetate electrophoresis of canine plasma after fibrinogen precipitation by ethanol

Background: In routine canine medicine, anticoagulated blood is often the only sample sent to laboratories for diagnostic purposes. This hampers the interpretation of protein electrophoretic tracings because plasma contains fibrinogen, which migrates in the β–γ region. In human medicine, fibrinogen can be precipitated from plasma using ethanol. Objectives: The purpose of this study was to assess ethanol precipitation as a method for removing fibrinogen from canine plasma so as to facilitate the interpretation of electorphoresis results. Methods: Blood samples collected from 40 dogs were divided into plain tubes and tubes containing EDTA (n=20) or lithium–heparin (n=20). An aliquot of plasma from each sample was incubated with ethanol at a final concentration of 100 mL/L. Cellulose acetate electrophoresis was then performed on serum, plasma, and plasma treated with ethanol. To verify the efficiency of ethanol treatment, fibrinogen was added to 5 canine serum samples at final concentrations of 2.5, 5.0, and 10.0 g/L, and electrophoresis was performed before and after ethanol treatment. Results: Visual analysis of electrophoretograms from ethanol‐treated samples confirmed the disappearance of the fibrinogen peak from the β₂‐globulin region. Treatment with ethanol caused a significant decrease in the percentage of β₂‐globulins and a significant increase in the percentage of α₂‐globulins. Absolute values of most electrophoretic fractions were significantly decreased in ethanol‐treated plasma compared with serum. Conclusions: Ethanol treatment successfully removed fibrinogen from canine plasma and normalized electrophoretic profiles, but probably also precipitated proteins other than fibrinogen. Ethanol treatment is recommended to facilitate visual identification of abnormal monoclonal peaks, but not for determining absolute protein concentrations in electrophoretic fractions.     

小麦Waxy蛋白亚基缺失类型鉴定方法的研究

建立适于我省面条专用小麦育种研究上应用的Waxy蛋白亚基缺失类型的鉴定技术;以改良十二烷基硫酸钠聚丙烯酰胺凝胶电泳技术(1-D-SDS-PAGE)为基础,分析凝胶性质、试验试剂、试验条件对电泳结果的影响,获得高效低成本、分辨效果佳、重复性好的鉴定方法。     

水牛梭形住肉孢子虫抗原的薄层等电聚焦行为分析

应用薄层聚丙烯酰胺等电聚焦电泳（ＩＦＥ）对水牛梭形住肉孢子虫（Ｓａｒｃｏｃｙｓｔｉｓｆｕｓｉｆｏｒｍｉｓ）抗原进行了分析。结果表明，经ＳｅｐｈａｄｅｘＧ－１００纯化的包囊抗原在电泳图谱上显示３条相距较近的带，等电点分别为６．３０，６．４５，６．６５；缓殖子纯化抗原仅出现１条带，等电点为６．４０     

Comparison of the Value of Pulsed-field Gel Electrophoresis,Random Amplified Polymorphic DNA and Amplified rDNA Restriction Analysis for Subtyping Taylorella equigenitalis

Eight strains of Taylorella equigenitalis were identified by a polymerase chain reaction using a primer pair specific to the 16S rDNA of T equigenitalis. These eight strains were chosen because they had previously been shown to represent eight distinct genotypes by pulsed-field gel electrophoresis analysis after separate digestion of the genomic DNA with ApaI or NotI. The eight strains could be classified into six or seven types by random amplified polymorphic DNA analysis using different kinds of primers. Amplified rDNA restriction analysis after separate digestion with five restriction enzymes, including AluI and MboI, of the 1,500 bp fragments of rDNA amplified by polymerase chain reaction did not discriminate the genomic variations among the eight strains of T equigenitalis. Thus, pulsed-field gel electrophoresis was shown to discriminate these eight organisms better than random amplified polymorphic DNA analysis, while amplified rDNA restriction analysis was found to be unsuitable for subtyping T equigenitalis.     

毛细管区带电泳测定饲料添加剂中酪蛋白磷酸肽含量的方法研究

利用毛细管区带电泳(CZE)对饲料添加剂中酪蛋白磷酸肽(CPP)样品进行分离，结果显示，用四硼酸钠缓冲溶液(20mmmol/L,pH9.2)及50cm×70μmi.d.石英毛细管柱，在工作电压30kV、检测波长200nm、柱温25℃的条件下，CPP得到较好的分离；同时，采用外标法对饲料添加剂样品中CPP各组分的含量进行了测定。     

Changes in meat texture of three varieties of squid in the early stage of cold storage

ABSTRACT: The present study examined the changes in texture and protein components during cold storage of different squid varieties. Raw oval squid, Japanese common squid and arrow squid were sliced fresh and the muscles were stored at 4°C for 0, 4, 8, 12, 18, 24, 48 and 120 h. The rheological measurements, protein components and amounts of collagen were examined. The adhesiveness of each squid increased significantly in the early stage of cold storage. In all varieties, penetration decreased at 4 h, which is considered to be rigor mortis, then increased. The amounts of total collagen, 20°C water-soluble collagen and 70°C water-soluble collagen did not change significantly in each variety during cold storage. Sodium dodecylsulfate–polyacrylamide gel electrophoresis (SDS-PAGE) pattern showed that the 580 kDa component gradually disappeared up to 48 h. The correlations between the amounts of 580 kDa component and adhesiveness or firmness were high. Models of fit based on chemical kinetics accurately expressed the behavior of adhesiveness, firmness and penetration showing that 63.2% of adhesiveness changes occurred in 13–19 h and that 63.2% of firmness changes occurred in 18–24 h.     

Meiotic and Isozymic Analyses of Tall Fescue × Giant Fescue Hybrids and Amphiploids1

The meiotic behavior of three tall fescue (Festuca arundinacea, 2n = 6x = 42) genotypes, giant fescue (F. gigantea, 2n = 6x = 42), and their reciprocal F₁ hybrids and C₁, amphiploids was evaluated to determine the parental genomic relationships. Isozyme banding patterns were used to confirm the parental identity of the hybrids and amphiploids. At meta-phase I, the parents had predominantly bivalent pairing. The hybrids had an average of 9.51 I, 16.02 II, 0.12 III, 0.02 IV, and the amphiploids had 2.17 I, 38.82 II, 0.60 III, 0.58 IV, 0.01 V—VIII. The prevalence of bivalent pairing in both hybrids and amphiploids suggested a homoeologous relationship between the six genomes, with four of the six being more closely related. Bivalent pairing in the amphiploids indicated genetic regulation of chromosome pairing. Zymograms were obtained for acid phosphatase (ACPH), alcohol dehydrogenase (ADH), glutamate oxaloacetate transaminase (GOT), malate dehydrogenase (MDH), 6-phosphogluconate dehydrogenase (6-PGD) and phosphoglucoisomerase (PGI). The three tall fescue and giant fescue parents had different zymograms for ACPH, MDH, 6-PGD and PGI; thus, the tall fescue parents of the hybrids and amphiploids could be determined based on the banding patterns of these four enzymes. Phenotypes were determined for ACPH-1, PGI-2 and 6-PGD-1. ACPH-1 may be used to follow the introgression of giant fescue chromatin into a certain tall fescue genotype.