气象因子对棉籽脂肪和蛋白质含量的影响

为确定影响棉籽脂肪和蛋白质含量的主要气象因子,量化主要影响因子的作用程度,研究于2005年在黄淮棉区(徐州、安阳)、长江下游棉区(淮阴、南京)多个生态点设置了不同品种的田间实验,供试品种为科棉1号和美棉33B.研究结果显示棉籽脂肪和蛋白质含量随生态点和开花期呈极显著变化.黄淮棉区棉籽脂肪含量、蛋白质含量最大值出现的棉铃开花期较长江下游棉区推迟.棉籽脂肪含量、蛋白质含量与气象因子的相关分析显示,二者与铃期气温日较差呈显著负相关关系,与铃期日均气温、平均日最高气温、平均日最低气温、平均地温显著正相关.通径分析和逐步回归分析显示,各气象因子中铃期平均日最低气温是最主要的影响因子.棉籽脂肪含量、蛋白质含量随铃期平均日最低气温的变化可用三次多项式拟合,决定系数均达到0.75以上.日最低气温22～23℃最适宜棉籽脂肪和蛋白质含量的形成,低于15℃时棉籽脂肪不能正常积累.     

去血红素细胞色素c的制备及其结构研究

在酸性条件下用硫酸银断裂马心细胞色素ｃ（以下简称ｃｙｔ．ｃ）的肽链与血红素相连的硫醚键,通过酸性丙酮抽提,巯基乙醇处理及超速离心等步骤纯化得去血红素的ｃｙｔ．ｃ（以下简称Ａｐｏ－ｃｙｔ．ｃ．）．Ａｐｏ－ｃｙｔ．ｃ与天然ｃｙｔ．ｃ相比,其酸性电泳迁移率明显降低,紫外－可见光谱在１９０￣２２０ｎｍ处吸收上升,荧光光谱的最大发射峰波长产生红移,同时ＣＤ谱中ａ螺旋的特征峰完全消失,这说明在ｃｙｔ．ｃ去血红     

去血红素细胞色素c的制备及其结构研究

在酸性条件下用硫酸银断裂马心细胞色素ｃ（以下简称ｃｙｔ．ｃ）的肽链与血红素相连的硫醚键,通过酸性丙酮抽提,硫基乙醇处理及超速离心等步骤纯化得去血红素的ｃｙｔ．ｃ（以下简称Ａｐｏ－ｃｙｔ．ｃ）。Ａｐｏ－ｃｙｔ．ｃ与天然ｃｙｔ．ｃ相比,其酸性电泳迁移率明显降低,紫外－可见光谱在１９０～２２０ｎｍ处吸收上升,荧光光谱的最大发射峰波长产生红移,同时ＣＤ谱中α螺旋的特征峰完全消失,这说明在ｃｙｔ．ｃ去血红素的过程中,蛋白质已由原来的紧密球状结构变成了较为松散、伸展的无规卷曲构象。因此,血红素对ｃｙｔ．ｃ天然构象的维持有着重要作用。     

无细胞蛋白质芯片的制备及其应用

蛋白质芯片是生物技术和功能蛋白组学的关键技术之一. 传统的生产蛋白的方 法周期长且费用高. 无细胞蛋白质合成系统和蛋白芯片的结合, 避免了基因的克隆、 蛋白的表达、纯化和保存等繁琐过程, 使整个无细胞蛋白芯片的制备过程快捷、迅速 和高效. 本文详细综述了无细胞蛋白质合成系统及其分类、无细胞表达系统在制备蛋 白质芯片方面的研究进展, 并探讨了无细胞蛋白质芯片在蛋白组学研究中的最新应用.     

无细胞系统原位制备蛋白质芯片及其应用

主要介绍了目前在生物芯片表面进行蛋白质无细胞表达与定向制备蛋白质芯片的研究进展,包括各种基因植入芯片的方法、蛋白质体外不同表达的途径、蛋白质固定的策略以及可能的应用发展前景等．蛋白质芯片以其高通量、高灵敏和检测迅速等优点正成为蛋白质组学研究中的重要工具之一．蛋白质的高效表达与纯化、蛋白质在芯片表面的有效固定与蛋白质活性的保持等内容是蛋白质芯片技术发展的关键．采用纳米生物技术与无细胞表达系统,已经可以在生物芯片表面通过植入基因的方式制备相关的蛋白质芯片,从而为蛋白质芯片的原位制备开辟了新的方向．     

棉籽蛋白质和油分含量预测的生态模型

为研究棉籽蛋白质和油分含量与环境因子间的定量关系,选择不同熟性棉花品种在长江流域下游棉区和黄河流域黄淮棉区各2个地点进行分期播种和施氮量试验,分析了品种、主要气象条件和施氮量对棉籽蛋白质和油分含量的影响.结果表明:棉籽蛋白质和油分含量的主要影响因子除品种外依次为铃期平均温度、太阳辐射量和施氮量;棉籽蛋白质和油分形成的最适宜铃期日均温分别为26.1℃和25.7℃;充足的光照不利于棉籽蛋白质和油分含量的提高;增加施氮量提高了棉籽蛋白质含量,降低了油分含量.建立了棉籽蛋白质含量与油分含量的生态模型,模型以品种、铃期平均温度、铃期日均太阳辐射量和施氮量为模型输入,简便易行.模型对棉籽蛋白质含量和油分含量预测的根均方差(RMSE)分别为2.03％和2.54％,具有较好的预测性.     

无细胞系统原位制备蛋白质芯片片及其应用

主要介绍了目前在生物芯片表面进行蛋白质无细胞表达与定向制备蛋白质芯片的研究进展,包括各种基因植入芯片的方法、蛋白质体外不同表达的途径、蛋白质固定的策略以及可能的应用发展前景等.蛋白质芯片以其高通量、高灵敏和检测迅速等优点正成为蛋白质组学研究中的重要工具之一.蛋白质的高效表达与纯化、蛋白质在芯片表面的有效固定与蛋白质活性的保持等内容是蛋白质芯片技术发展的关键.采用纳米生物技术与无细胞表达系统,已经可以在生物芯片表面通过植入基因的方式制备相关的蛋白质芯片,从而为蛋白质芯片的原位制备开辟了新的方向.     

褐藻裙带菜色素—蛋白质复合物的分离与命名

以非离子去污剂癸基－Ｎ－甲基葡萄糖胺为增溶剂,采用聚丙烯酰胺凝胶电泳技术从褐藻裙带菜（Ｕｎｄａｒｉａ ｐｉｎｎａｔｉｆｉｄａ Ｈａｒｖ．）的类囊体膜上分离到８种色素－蛋白质复合物。根据其表观分子量、光谱特性和多肽分析结果,并以高等植物菠菜（Ｓｐｉｎａｃｉａ ｏｌｅｒａｃｅａ Ｌ．）为对照,按照Ａｎｄｅｒｓｏｎ命名系统,８种色素－蛋白质复合物分别命名为ＣＰⅠ ａ、ＣＰⅠ、ＣＰａ、ＬＨＣ１、ＬＨＣ２、     

裙带菜与菠菜的色素-蛋白质复合体的比较研究

裙带菜ＰＳＩ复合体的７７Ｋ荧光发射光谱与菠菜的明显不同,缺少７３０ｎｍ长波荧光峰,位于７１５ｎｍ处,其捕光色素－蛋白质复合体有墨角藻黄素－叶绿素ａ／ｃ－蛋白质复合体和叶绿素ａ／ｃ－蛋白质复合体两种,菠菜只有一种叶绿素ａ／ｂ－蛋白质复合体。     

七鳃鳗口腔腺蛋白质功能的研究进展

寄生期的七鳃鳗为水中吸血鬼,依靠吸食宿主血肉为生。近年来,陆续有研究报道从七鳃鳗口腔腺分泌液中鉴定出多种与抗凝、免疫逃逸、抗血管新生、镇痛以及氧化应激等有关的活性蛋白质。明确七鳃鳗口腔腺内活性蛋白质的特性及生物学功能将有助于阐明七鳃鳗独特的寄生机制,并为这些活性蛋白质的应用奠定理论基础。     

固定化脂肪酶催化毛棉籽油制备生物柴油

研究了固定化脂肪酶Lipozyme TL IM和Novozym435催化毛棉籽油和乙酸甲酯制备生物柴油的过程。通过向反应体系中添加甲醇,可减少乙酸的抑制,明显提高生物柴油得率,确定最佳反应条件为:正己烷作溶剂,乙酸甲酯与油摩尔比9:1,添加油重3%的甲醇、油重10%的LipozymeTLIM和5%的Novozym435复合使用,温度55°C,反应8h,生物柴油得率达到91.83%。最后探索了酶催化毛棉籽油合成生物柴油的动力学,得到动力学方程。     

A method for whole protein isolation from human cranial bone

The presence of the dense hydroxyapatite matrix within human bone limits the applicability of conventional protocols for protein extraction. This has hindered the complete and accurate characterization of the human bone proteome thus far, leaving many bone-related disorders poorly understood. We sought to refine an existing method of protein extraction from mouse bone to extract whole proteins of varying molecular weights from human cranial bone. Whole protein was extracted from human cranial suture by mechanically processing samples using a method that limits protein degradation by minimizing heat introduction to proteins. The presence of whole protein was confirmed by western blotting. Mass spectrometry was used to sequence peptides and identify isolated proteins. The data have been deposited to the ProteomeXchange with identifier PXD003215. Extracted proteins were characterized as both intra- and extracellular and had molecular weights ranging from 9.4 to 629 kDa. High correlation scores among suture protein spectral counts support the reproducibility of the method. Ontology analytics revealed proteins of myriad functions including mediators of metabolic processes and cell organelles. These results demonstrate a reproducible method for isolation of whole protein from human cranial bone, representing a large range of molecular weights, origins and functions.     

Rapid estimation of potato tuber total protein content with coomassie brilliant blue G-250

Summary A new method for measuring protein with Coo-massie Brilliant Blue G-250 has been adapted for use as a screening method in a potato tuber protein improvement breeding program. The method is simple, fast and inexpensive, and has successfully estimated the total protein content of a broad range of tuber genotypes having dissimilar amino acid profiles and tuber maturities. Correlation between the Coomassie method and a modified micro-Kjeldahl method, the standard method used in the potato breeding program, was 0.93. Free amino acids and other compounds which interfere with other methods for measuring protein do not interfere with the Coomassie Brilliant Blue procedure.This research was supported in part by the Rockefeller Foundation. Scientific Journal Series Article # 10,157 of the Minnesota Agricultural Experiment Station     

C群脑膜炎球菌多糖纯化方法的改进

将C群脑膜炎球菌粗多糖的纯化改进为用1:1容量冷酚提取的生产工艺。结果表明,改进后的方法去除蛋白质效果同样能够达到《中国药典》2005版(三部)的要求,总体结果优于改进前。同时能扩大处理量而降低了生产成本,适合规模化生产。     

雷蒙德氏棉和亚洲棉基因组数据中LPAAT基因家族的发掘及其同源基因在陆地棉材料中的表达分析

溶血磷脂酸酰基转移酶(Lysophosphatidic acid acyltransferase, LPAAT)是油脂合成途径中的一个关键酶,能催化溶血磷脂酸转变为磷脂酸。本研究从雷蒙德氏棉(G. raimondii, D5)和亚洲棉(G. arboreum, A2)的基因组数据中得到17个LPAAT基因家族成员。利用生物信息学方法对二倍体棉花LPAAT基因进行基因结构、染色体分布以及系统进化分析。结果表明,LPAAT基因家族根据亲缘关系的远近可以分为不同的亚家族,各亚家族中LPAAT基因具有相似的基因结构;LPAAT家族基因编码的氨基酸序列具有3个保守基序,其中包括ΦFPEGTR-G结合位点和Φ-NHQS-ΦDΦΦ催化位点;通过对不同物种的LPAAT基因家族进行系统进化分析可知,不同物种中的LPAAT在进化中存在较大差异。基于陆地棉(G. hirsutum)不同发育时期的胚珠RNA-seq数据库和qRT-PCR表达分析,发现LPAAT基因可能对脂肪积累起到积极作用。本研究结果有助于了解棉属植物LPAAT基因家族的功能,以期从中选取较好的LPAAT基因进行进一步功能验证。     

Purification and Separation of A and B Forms of N-Acetyl-β-D-Hexosaminidase from Human Aorta

Human aorta has been shown to possess multiple forms of N-Acetyl-6-D-hexosaminidase (β-2-acetamido-2-deoxy-D-glucoside-acetamido-deoxyglucohydro-lase, EC 3.2, 1.30). The enzyme was separable, by gel electrophoresis, into 2 enzymatically active bands representing A and B forms. By gel electro-focussing, A and B forms were further subdivided into at least 5 and 8 bands, respectively. The B form consisted of 4 bands (B₁) and 4 bands (B₂), which were not inactivated at 50° for 3 hr. (at pH 4.4) in the presence of serum; whereas, the 5 bands found in A form were completely inactivated. All forms of the enzyme were active towards naphthol-AS-BI-N-acetyl-β-D-glucosaminide and the corresponding galactosaminide (about one-eighth of the hydrolysis rate of the former), suggesting each single enzyme acts on both substrates. The N-acetyl-hexosaminidases of bull epididymis, by comparison, were also found to be active towards both substrates and to possess 13 bands having pis more alkaline than those of the B form of the human enzyme, By heat inactivation we found that the aortic enzyme consisted of 51% of A and 49% of B (B₁ + B₂ .). Neuraminidase had no effect on either form of the aortic preparation. Both forms were partially purified and separated by conventional methods. They required BSA for their maximal activity; the A form being more dependent BSA than the B form, With PNP-N-acetyl-β-D-glucosaminide and the corresponding galactosaminide, Km of 1.04 mH and 0.54 mM, respectively, for A form and of 1.74 and 1.48 mM, respectively, for B form were obtained. While the purified B form was stable and did not transform into other species, the purified A form gradually transformed into B form as well as into other new forms during storage at -20°.     

Preparative Cell Electrophoresis

Abstract

A simple method is described for preparative cell electrophoresis. Solid glass beads (? 0.1 mm diameter) are used as packing material in a cylindrical glass column, the interstices of which contain a citric acid-phosphate buffer of pH 7.6 and 0.015 ionic strength. Cell mixtures containing ? 6 × 10⁹ erythrocytes in 0.2 ml are electrophoresed at 25 V/cm for 1–2 hours after which the column contents are extruded and the separated cell fractions recovered. Complete separation was achieved between mixtures of human and chicken erythrocytes and untreated and papain-treated human erythrocytes. The electrophoretic mobilities of cells subjected to this procedure are in good agreement with previously published mobilities, obtained by microelectrophoresis.     

Feed intake, milk production and composition of crossbred cows fed with insect-protected Bollgard II® cottonseed containing Cry1Ac and Cry2Ab proteins

Twenty crossbred lactating multiparous cows were used in a 28-day study to compare dry matter intake (DMI), milk yield, milk composition and Bacillus thuringiensis (Bt) protein concentrations in plasma when fed diets containing Bollgard II® cottonseed (BGII) or a control non-genetically modified isogenic cottonseed (CON). Bollgard II cottonseed contains the Cry1Ac and Cry2Ab insecticidal proteins that protect cotton plants from feeding damage caused by certain lepidopteran insects. Cows were assigned randomly to the BGII or CON treatments after a 2-week adjustment period. Cows consumed a concentrate containing 40% crushed cottonseed according to milk yield and green maize forage ad libitum. All cows received the same diet but with different crushed cottonseed sources. Cottonseed was included to provide approximately 2.9 kg per cow daily (dry matter basis). The ingredient composition of the concentrate was 40% crushed cottonseed, 15% groundnut cake, 20% corn, 22% wheat bran, 1% salt and 2% mineral mixture. Milk and blood plasma were analyzed for Cry1Ac and Cry2Ab proteins. DMI, BW, milk yield and milk components did not differ between cows on the BGII and CON treatments. Although milk yield and milk fat percentage were not affected by treatment, 4% fat-corrected milk (FCM) production and FCM/kg DMI for cows on the BGII treatment (14.0 kg/cow per day, 1.12 kg/kg) were significantly improved compared with cows on the CON treatment (12.1 kg/cow per day, 0.97 kg/kg). Gossypol contents in BGII cottonseed and conventional cottonseed were similar. Cry1Ac and Cry2Ab2 proteins in Bollgard II cottonseed were 5.53 and 150.8 μg/g, respectively, and were not detected in the milk or plasma samples. The findings suggested that Bollgard II cottonseed can replace conventional cottonseed in dairy cattle diets with no adverse effects on performance and milk composition.