高纯度大豆种子线粒体的分离

利用不连续Percoll梯度分离得到高纯度的大豆（Glycine max）种子线粒体.线粒体制剂中没有检测到胞液、过氧化物体和叶绿素的污染.线粒体的完整性达到97%以上,在0～4℃下至少稳定2小时.     

小麦小花高纯度线粒体的分离及其蛋白质双向电泳体系建立

应用差速离心和Percoll不连续密度梯度法分离纯化小麦三核期小花线粒体. 在裂解液选择、IPG胶条pH值范围、SDS-PAGE胶浓度及蛋白质上样量等方面对线粒体蛋白质双向电泳体系进行探索和优化,确立了一套适用于小麦小花高纯度完整线粒体的分离方法及其蛋白质双向电泳的技术体系. 结果表明,采用20%、24%和40% Percoll密度梯度和28% Percoll自形成密度高速离心体系,获得了有活性、高纯度且较完整的线粒体;经TCA-丙酮法提取蛋白,以7 mol/L尿素,2 mol/L硫脲,4% CHAPS(W/V),65 mmol/L DTT,0.5% IPG缓冲液(V/V),0.001% 溴酚蓝(W/V)裂解液溶解蛋白,采用17 cm,pH 4～7 IPG胶条和11% SDS-PAGE分离胶,上样量为160 μg,硝酸银染色法,更适合小麦小花线粒体蛋白质组双向电泳分离. 经PDQuest 2DE 8.0.1软件包统计分析,在2-DE图谱上分辨出约150个蛋白点,蛋白点清晰呈圆形,无横条纹干扰,这为利用双向电泳技术在亚细胞水平对线粒体进行蛋白质组学研究与分析奠定了基础,更为进一步分析研究线粒体与雄性不育的关系提供了理论与技术支撑.     

一种改良的大豆线粒体DNA提取方法

以大豆(Glycine max (L.) Merrill)黄化苗为材料,通过优化提取线粒体DNA(mtDNA)时差速离心过程中的离心力和离心时间,以及纯化过程中设置不同的蔗糖密度梯度和裂解液浓度,结合高盐法去除蛋白质,改良大豆mtDNA的提取方法。结果表明,该方法提取的mtDNA浓度和纯度较高,无叶绿体和核基因组DNA的污染,可用于后续大豆线粒体基因组的相关研究。     

PVA和PEG预处理对大豆种子在低温吸胀过程中胚根线粒体发育和超微结构的影响

电镜观察发现,大豆种子在刚开始萌发时胚根细胞中未能见到线粒体,线粒体是在种子萌发过程中逐渐出现的,由原质体再分化发育而成。对照胚根细胞内原质体在低温吸张过程中明显膨胀,在回温后胚根细胞中原质体仍不能发育成线粒体,甚至网状膜结构破坏,呈空泡化;经聚乙烯醇(PVA)和聚乙二醇(PEG 6000)预处理的大豆种子在同样条件下线粒体能继续发育,在回温后预处理胚根细胞中线粒体发育良好,具有明显的双层膜和管状嵴的结构。这些结果表明,在低温吸胀过程中原质体能够继续再分化发育成线粒体是提高大豆种子活力和抗冷力的重要原因。     

高纯度大豆卵磷脂对中国仓鼠肺细胞染色体畸变作用

目的研究高纯度大豆卵磷脂对中国仓鼠肺细胞（cHL）染色体畸变作用。方法测定高纯度大豆卵磷脂对CHL细胞的半数抑制浓度（IC50）,根据IC50设立不同剂量组,进行正式试验,分别观察高纯度大豆卵磷脂接触CHL6h,24h及加S9后6h染色体的畸变情况,根据标准进行结果判定。结果染毒6h,24h及加S9后染毒6h染色体畸变为阴性。结论高纯度大豆卵磷脂不能引起CHL细胞染色体产生畸变作用。     

栽培大豆中一个线粒体atp６基因的分离与鉴定

线粒体ＡＴＰ酶（mtATPase)复合体在高等植物生命活动中起重要作用。从栽培大豆（Glycine max(L.)Merr.)中分离鉴定了一个新的mtATPase第六亚基（ＥＣ３．６．１．３４）基因（atp６）,它编码具２２３个氨基酸的ＡＴＰ６亚基,是所有已克隆的atp６基因中最短的一个,并把它命名为atp６copy3(atp６-3)。通过对９种栽培大豆的ＰＣＲ分析及序列分析表明atp６－３广泛在于栽培大豆中,以atp６－３为探针对大豆重组近交系的ＲＦＬＰ分析初步表明栽培大豆线粒体有父性遗传的可能性。水杨酸处理明显抑制atp６的表达,并对其可能作用进行了鉴定。     

微量大豆种子基因组DNA的快速制备

用改良的CTAB法,从微量大豆种子样品中快速提取了基因组DNA,并从大豆基因组中扩增到了大豆蛋白酶抑制剂基因.     

光对绿豆种子和叶片分离线粒体耗氧的影响

实验结果表明：照光时绿豆叶片分离线粒体通过细胞色素氧化酶途径的NADH氧化部分受阻,电子转向交替途径。不产生能量．不受能荷控制的NADH氧化途径有利于绿色细胞线粒体在光合作用时执行其提供碳架的功能。看来绿色细胞线粒体本身具有对光的敏感性,在照光时调节呼吸途径以适应其功能的转换。呼吸途径的转换机制目前还不清楚。绿豆种子线粒体与叶片线粒体不同,没有上述的这种对光的反应。     

大豆花叶病毒种子传毒率测定方法的比较

用苗期症状观察和酶联免疫吸附试验(ELISA)两种方法检查了大豆种子内的大豆花叶病毒(sMV)的传毒率及带毒率,并对两种方法所得的结果进行了比较。带毒大豆种子产生的病苗,其症状主要有花叶、卷叶、叶脉束状、叶脉坏死、凸斑和单叶扭曲等类型。苗期症状观察得到的种子传毒率,与用ELISA法检查去种皮大豆种子的带毒率高度吻合,相关系数r=0.92(n=31),说明此两种方法检查种子传(带)毒率具有相同的生物学和病理学意义。 本文提出了种子“群体病毒浓度”的概念。“群体病毒浓度”=群体内病毒总量/群体内种子总数。38个处理组合和3,591粒种子逐粒用ELISA法检查表明,“群体病毒浓度”与该群体的种子传毒率呈正相关,r=0.93(n=38)。将种子群体作为一个整体用ELISA法检查的结果也证明,“群体病毒浓度”与种子传毒率呈直线相关。因此认为可以用ELISA法对种子群体直接进行测定来估计种子的传毒率。     

Isolation of Ribonucleic Acids Having Template Activities from Particulate Components of Soybean Seeds

Ribonucleic acids having template activities were obtained from particulate components prepared from the postribosomal supernatant of soybean seeds. These RNA were 9 S and 18 S in size, and these corresponded to the components (9 S, 18 S) of high molecular weight RNA (H–RNA) prepared from the supernatant of 100,000×g centrifugation. The sizes of the particulate components were 37 S and 59 S, respectively. Larger particles contained 18 S and 9S RNA, and smaller particles contained 9S RNA, but not 18 S RNA. Those particulate components differed in absorption pattern and in the behaviour on sucrose gradient centrifugation depending on the concentration of Mg²⁷⁺ from the subunits of ribosomes.     

Isolation and Structural Elucidation of DDMP-Conjugated Soyasaponins as Genuine Saponins from Soybean Seeds

The composition and the structures of native “group B saponin” in soybean seeds were reinvestigated. Five kinds of saponins named soyasaponins αg, βg, βa, γg, and γa, according to elution order from HPLC, were isolated and the structures were characterized as 2,3-dihydro-2,5-dihydroxy-6-methyl-4H-pyran-4-one (DDMP) attaching through an acetal linkage to the C-22 hydroxyl of the aglycones of soyasaponins V, I, II, III, and IV, respectively, by UV, IR, MS, and NMR. DDMP-conjugated saponins were detected as major saponin constituents by extraction under mild conditions, and soyasaponins I–V were not detected. Therefore it was strongly suggested that these DDMP-conjugated saponins were genuine saponins in the intact soybeans.     

Isolation of Cerebroside from Pea Seeds

Cerebroside was isolated from pea (Pisum sativum L.) seeds by solvent extraction, mild alkaline hydrolysis and silicic acid column chromatography. The purified material was identified as cerebroside by thin-layer chromatography and infrared spectrometry. Hydrolysates of the cerebroside were divided into fatty acid, sphingosine base and sugar fractions, and analysed, mainly by gas-liquid chromatography. The major fatty acid components were hydroxytricosanoic, hydroxydocosanoic and hydroxytetracosanoic acids. Dihydrosphingosine was the predominant sphingosine base. Only glucose was detected in the sugar fraction. Based on these results, one of the major species of pea cerebroside is suggested to be N-hydroxytricosanoyl-glucopyranosyl-dihydrosphingosine.     

Polysaccharides of Soybean Seeds

A polysaccharide fraction extracted from soybean seeds with boiling water was examined by several fractionation methods on ultracentrifugal criteria. Four components were found by a column chromatography using TEAE-cellulose or by a paper electrophoresis. Acetone-precipitation, fractionation by conversion into acetyl derivative, and copper-complex-precipitation were unsatisfactory to fractionate into the components. The major component (70%) isolated was an arabinogalactan containing residues of arabinose and galactose in the approximate proportion of 1 : 2 and having molecular weight of 3.3×10⁵.     

Polysaccharides of Soybean Seeds

Partial acid hydrolysate of the “hot-water-extract” fraction of soybean seed polysaccharides contained a homologous series of galacto-oligasaccharides as a major component group. Two of them were isolated by column chromatography. They gave, on methylation followed by acid hydrolysis, 2,3,4,6-tetra-, and 2,3,6-tri-O-methyl D-galactose, and were, therefore, 1,4-linked galacto-di- and trisaccharides, respectively. They were hydrolyzed with human saliva to liberate D-galactose but not with brewer’s yeast. The alditols derived from these oligosaccharides showed infrared absorptions at 885 and 895 cm^?1, respectively. These two results were strong evidences for the presence of β-linkages in the molecules of the oligossacharides. The optical rotation and the melting point of the disaccharide agreed with those of the β-1, 4-linked galactodisaccharide hitherto reported. Thus d-galacto-pyranosyl residues in the arabinogalactan are probably connected mainly by β-1,4-linkage.     

Polysaccharides of Soybean Seeds

Methylation of hot-water-extract fraction of soybean seed polysaccharides by the Haworth’s method and then by the Purdie’s method followed by fractional extraction afforded a fully methylated arabinogalactan which gave on complete hydrolysis 2,3,5-tri-, and 2,3-di-O-methyl l-arabinose and 2,3,6-tri-, and 2,6-di-O-methyl d-galactose in the approximate proportion of 1 : 1 : 3 ~ 4: 1, and on controlled acid methanolysis 2,3,5-tri-, and 2,3-di-O-methyl l-arabinose in about equal proportion. Residual undegraded polysaccharide gave mainly 2,3,6-tri-O-methyl d-galactose on remethylation and hydrolysis.     

An alpha-Galactosidase with Hemagglutinin Properties from Soybean Seeds

Soybean (Glycine max L.) seeds contain a galactose-binding protein which displays two activities: (a) an alpha-galactosidase activity and (b) a hemagglutinin activity. The alpha-galactosidase-hemagglutinin was purified to homogeneity by conventional protein purification procedures and also by affinity chromatography. This protein can be easily separated from soybean agglutinin, the N-acetyl-d-galactosamine-specific lectin in soybean. Further, these two agglutinins show no immunological relatedness. The alpha-galactosidase-hemagglutinin can be reversibly converted by pH changes from a tetrameric form which displays both enzymic and hemagglutinin activities to a monomeric form which displays enzymic activity only. Although both the monomeric and tetrameric forms are enzymically active, they display different pH optima and carbohydrate specificities.