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1.
The nucleotide sequence of one of the Escherichia coli tyrosine-transfer ribonucleic acids was determined in order to compare its sequence with that of yeast tyrosine-transfer ribonucleic acid. Forty-four positions of both transfer ribonucleic acids are occupied by the same nucleotides if they are arranged in the manner shown here. The information obtained suggests that the conformation of transfer ribonucleic acid molecules may be a greater contributing factor than a specific nucleotide sequence in the interaction of transfer ribonucleic acid with its corresponding aminoacyl-transfer ribonucleic acid synthetase. 相似文献
2.
Cytokinin activity: localization in transfer RNA preparations 总被引：15，自引：0，他引：15
F Skoog D J Armstrong J D Cherayil A E Hampel R M Bock 《Science (New York, N.Y.)》1966,154(754):1354-1356
Transfer RNA from yeast, liver, and Escherichia coli has cytokinin activity in the tobacco callus bioassay, whereas ribosomal RNA from yeast is inactive. In contrast to fractions of yeast transfer RNA rich in serine acceptor and cytokinin activity, preparations (70 to 90 percent pure) of arginine transfer RNA(2), glycine transfer RNA, phenylalanine transfer RNA, and valine transfer RNA(1) and of highly purified alanine transfer RNA from yeast were inactive at concentrations of 20 to 2500 micrograms per liter. One molecule of 6-(gamma,gamma-dimethylallylamino) purine per 20 molecules of yeast tRNA would account for the observed cytokinin activity. The number of major molecular species contributing to cytokinin activity of transfer RNA, therefore, must be small. 相似文献
3.
Native and renatured transfer ribonucleic acid 总被引：3，自引：0，他引：3
Transfer ribonucleic acid, isolated under conditions in which the original macromolecular structure is never denatured, is indistinguishable from transfer ribonucleic acid prepared by conventional methods involving denaturing steps. This finding is consistent with the absence of direct genetic control of the formation of macromolecular structure of transfer ribonucleic acid. 相似文献
4.
Aminoacyl transfer ribonucleic acid synthetases from cell-free extract of Plasmodium berghei 总被引：2，自引：0，他引：2
Aminoacyl transfer ribonucleic acid synthetases for leucine tyrosine, histidine, valine, proline, threonine, and lysine were obtainnned from cell-free extract of Plasmodium berghei. The leucyl-tRNA synthetase cane charge tRNA from liver or Escherichia coli with leucine-c(14), liver tRNA being a better substrate. The amount of aminoacylation increses linerly with respect to the quantity of tRNA added from either source and is dependent on the amount of enzyme added. The rate of aminoacylation is constant for 10 minutes and then decreases. It is enhanced by polyvinylsulfate. One-tenth millimoler pyrimethamine, hydroxystilbamidine, quinacrine, and acriflavine inhibited the formation of C(14)-valyl-tRNA. Species specificity between tRNA and its charging enzyme with respect to the recognition site is discussed. 相似文献
5.
Acquisition of a behavioral response motivated by shock was enhanced in rats chronically treated with yeast ribonucleic acid, and resistance to extinction was greater in rats so treated than in controls. This extends the role of ribonucleic acid to include a behavioral effect in laboratory mammals treated with a purified preparation from yeast. 相似文献
6.
采用去离子水抽提、热变性、硫酸铵盐析及亲和层析和分子筛层析等方法,从传统药用植物大决明种子中得到1种胰蛋白酶抑制剂.SDS-PAGE和MALDI-TOF检测为单一多肽链,其精确分子量为19812.55 Da.氨基酸组成分析表明,该抑制剂中异亮氨酸、缬氨酸和苯丙氨酸含量最高.肽指纹图谱中有8个主要的信号簇.模拟胃液实验和荧光光谱结果表明,二硫键和赖氨酸残基对于维持该抑制剂的天然活性构象必不可少.当该抑制剂被还原或赖氨酸残基被修饰后,其抑制活性及对胃蛋白酶的抗性会有较大程度的丧失.通过串联质谱(MS/MS)测定该抑制剂的部分氨基酸序列,并与多种豆科Kunitz蛋白酶抑制剂进行比对,发现有较高的同源性.同时,该抑制剂能够抑制菜青虫中肠类胰蛋白酶的活力,其抑制效果与大豆Bowman-Birk蛋白酶抑制剂的抑制效果相当. 相似文献
7.
本试验测定了无花果扦插苗在300mmol L~(-1)NaCl 处理的48小时期间叶片中17种游离氨基酸含量的变化。结果表明:除脯氨酸大量增加外,异亮氨酸、缬氨酸、苏氨酸、组氨酸、亮氨酸、苯丙氨酸、甘氨酸、丙氨酸、胱氨酸、丝氨酸和赖氨酸等11种游离氨酸也有不同程度的增加;10ppm 放线菌素 D 或环己亚胺明显抑制脯氨酸、异亮氨酸、苏氨酸、苯丙氨酸、丝氨酸及亮氨酸的积累,而10ppm 红霉素则不能抑制其积累,推测积累过程与氨基酸合成酶的合成有关。 相似文献
8.
[目的]为东北刺人参的开发利用奠定基础。[方法]分别用氨基酸自动分析仪和原子吸收分光光度计测定东北刺人参中多种氨基酸和元素的含量。[结果]东北刺人参茎和根的氨基酸总含量分别为3．6135％和3．2906％,天冬氨酸、谷氨酸、亮氨酸、苏氨酸、缬氨酸、蛋氨酸、异亮氨酸、苯丙氨酸、赖氨酸的含量分别为0．4501、0．4486、0．3021、0．2016、0．2259、0．0390、0．1744、0．2082、0．2502和0．3476、0．4036、0．2752、0．1727、0．2134、0．0394、0．1570、0．1801、0．2439mg／kg,必需氨基酸约占氨基酸总量的40％。东北刺人参茎的元素总合量比根高。东北刺人参茎和根中常量元素Ca、K、Na、Mg的含量分别为15045．19、3698．97、1310．95、474．23和14326．47、1957．22、1438．51、586．36mg／kg,微量元素Zn和Cu的含量分别为355．45、62．64和250．79、40．73mg／kg。『结论1该研究为东北刺人参产品的开发研制奠定了理论基础。 相似文献
9.
［目的］为科学地开发利用刻叶刺儿菜的食用及药用价值奠定基础。［方法］ 采用氨基酸自动分析仪和原子吸收分光光度计测定分析野生刺儿菜和刻叶刺儿菜中氨基酸与微量元素的含量。［结果］ 天门冬氨酸、苏氨酸、丝氨酸、谷氨酸、甘氨酸、丙氨酸、缬氨酸、蛋氨酸、亮氨酸、异亮氨酸、酪氨酸、苯丙氨酸、赖氨酸、组氨酸、精氨酸和脯氨酸在刺儿菜中的含量分别为0.17%、0.09%、0.08%、0.19%、0.10%、0.10%、0.09%、0.01%、0.16%、0.07%、0.06%、0.10%、0.13%、0.04%、0.09%和0.07%,在刻叶刺儿菜中的含量分别为0.17%、0.08%、0.08%、0.18%、0.09%、0.10%、0.09%、0.01%、0.15%、0.07%、0.06%、0.10%、0.13%、0.04%、0.09%和0.06%。钾、钠、钙、镁、铜、锌、铁和锰在刺儿菜中的含量分别为15.376、0.509、142.265、10.701、0.016、0.071、0.271和0.045 mg/g,在刻叶刺儿菜中的含量分别为16.110、1.141、144.834、9.305、0.020、0.053、0.294和0.050 mg/g。［结论］ 刺儿菜和刻叶刺儿菜都含有丰富的氨基酸和人体所需的多种微量元素。 相似文献
10.
When plasma tryptophan is elevated by the injection of tryptophan or insulin, or by the consumption of carbohydrates, brain tryptophan and serotonin also rise; however, when even larger elevations of plasma tryptophan are produced by the ingestion of protein-containing diets, brain tryptophan and serotonin do not change. The main determinant of brain tryptophan and serotonin concentrations does not appear to be plasma tryptophan alone, but the ratio of this amino acid to other plasma neutral amino acids (that is, tyrosine, phenylalanine, leucine, isoleucine, and valine) that compete with it for uptake into the brain. 相似文献
11.
The relative rates of racemization for amino acid residues at the NH(2) and COOH ends of 37 different dipeptides were determined. In nine dipeptides containing alanine, leucine, phenylalanine, aspartic acid, and methionine, the amino acid residue racemized faster at the COOH-terminal position than at the NH(2)-terminal position (COOH > NH(2)). The sterically hindered amino acids isoleucine and valine showed NH(2) > COOH. Six proline dipeptides showed NH(2) > COOH. Intramolecular effects have been invoked to explain these surprising results. 相似文献
12.
Freundlich M 《Science (New York, N.Y.)》1967,157(3790):823-825
alpha-Aminobutyric acid is activated but not transferred to valine-specific transfer RNA and is unable to repress the isoleucine-valine enzymes in Escherichia coli strain W. alpha-Amino-beta-chlorobutyric acid is activated and transferred to valine-specific transfer RNA and completely replaces valine in repression. 相似文献
13.
普洱茶中氨基酸与贮期、级别及品质关系的研究 总被引：1，自引：0，他引：1
以不同储藏时期、不同级别的普洱茶为材料,对氨基酸总量及组分含量进行理化分析.结果表明,普洱茶贮藏过程中随着贮藏时间的加长,普洱茶中游离氨基酸总量明显降低,其中丝氨酸、甘氨酸、丙氨酸、异亮氨酸、亮氨酸、组氨酸已基本消减,仅检出精氨酸、脯氨酸、赖氨酸、苯丙氨酸、酪氨酸、缬氨酸、胱氨酸,其含量变化无明显规律性;从7个级别标准样中检出15种氨基酸,未检出苏氨酸、组氨酸、色氨酸,其中氨基酸含量最高的组分是精氨酸,其次是天冬氨酸、赖氨酸、苯丙氨酸、酪氨酸、谷氨酸.茶氨酸在普洱茶中的含量与其它茶类不同,其含量仅占普洱茶中游离氨基酸总量的30％左右.与其它茶类中氨基酸含量相比,普洱茶具有氨基酸种类齐全,营养配比全面、均衡的特点,在保健方面有特殊的意义. 相似文献
14.
【目的】研究刺葡萄发酵过程中氨基酸的化学组成与果香酯类物质生成的关联,为刺葡萄酒增香酿造提供理论指导。【方法】试验以刺葡萄品种‘湘珍珠’为研究对象,以‘赤霞珠’葡萄为对照,添加酿酒酵母启动酒精发酵,每隔24 h取样,分别采用HPLC和GC-MS方法测定氨基酸和酯类物质的组成及含量,并通过Pearson相关性分析建立二者之间的数学关联。【结果】刺葡萄中除脯氨酸之外的氨基酸总体含量为‘赤霞珠’葡萄的3倍,天冬氨酸、缬氨酸、谷氨酸、γ-氨基丁酸、精氨酸含量分别达到‘赤霞珠’葡萄中对应氨基酸含量的2.4倍、2.2倍、4.2倍、7.7倍和3倍,但丙氨酸、苯丙氨酸、异亮氨酸含量仅为‘赤霞珠’葡萄中对应氨基酸含量的10%、35%和20%。刺葡萄发酵产生的乙酸酯、短链脂肪酸乙酯、中链脂肪酸乙酯含量仅为‘赤霞珠’葡萄发酵所得上述酯类物质的55%、11%和69%。Pearson相关性分析显示,刺葡萄发酵过程中丙氨酸、苯丙氨酸、异亮氨酸与乙酸酯、脂肪酸乙酯的相关性系数在0.552—0.837,较‘赤霞珠’葡萄发酵体系中相应的相关性系数显著偏低,这可能与刺葡萄酒果香酯类物质含量偏低有关。【结论】刺葡萄中含量偏低的丙氨酸、苯丙氨酸、异亮氨酸可能限制了刺葡萄酒发酵体系中果香酯类物质的积累。 相似文献
15.
The protein content and amino acid composition for 17 wheat-related species （WRS） and three common wheats （control） were determined and analyzed, and the essential amino acids （EAAs） in WRS were evaluated according to FAO/WHO amino acid recommendations. The results showed that the mean protein content for WRS was 16.67%, which was 23.21% higher than that for the control. The mean contents （g 100 g^-1 protein） of most amino acids for WRS were lysine 2.74%, threonine 2.83%, phenylalanine 4.17%, isoleucine 3.42%, valine 3.90%, histidine 2.81%, glutamic acid 29.96%, proline 9.12%, glycine 3.59%, alanine 3.37%, and cysteine 1.57%, which were higher than those for the control. The contents of the other 6 amino acids for WRS were lower than those for the control. The materials （Triticum monococcum L., Triticum carthlicum Nevski, and Triticum turgidum L.） contained relatively high concentration of the most deficient EAAs （lysine, threonine, and methionine）. Comparing with FAO/WHO amino acid recommendations, the amino acid scores （AAS） of lysine （49.8%）, threonine （70.7%）, and sulfur-containing amino acids （74.8%） were the lowest, which were considered as the main limiting amino acids in WRS. It was observed that the materials with Triticum urartu Turn. （AA） and Aegilops speltoides Tausch. （SS） genomes had relatively high contents of protein and EAA. The contents of protein （16.91%）, phenylalanine （4.78%）, isoleucine （3.53%）, leucine （6.16%）, and valine （4.09%） for the diploid materials were higher than those for the other materials. These results will provide some information for selecting parents in breeding about nutrient quality and utilization of fine gene in wheat. 相似文献
16.
Actinomycin D inhibits the synthesis of ribonucleic acid in L cells and the yield of vaccinia virus containing deoxyribonucleic acid, but it does not inhibit cellular deoxyribonucleic acid synthesis or the multiplication of Mengo virus containing ribonucleic acid. These observations serve to distinguish the replication of viral ribonucleic from ribonucleic acid synthesis which is controlled by viral or cellular deoxyribonucleic acid. 相似文献
17.
Irreversible inhibition of nuclear exoribonuclease by thymidine-3'-fluorophosphate and p-haloacetamidophenyl nucleotides 总被引：5，自引：0，他引：5
M B Sporn D M Berkowitz R P Glinski A Ash C L Stevens 《Science (New York, N.Y.)》1969,164(886):1408-1410
Exoribonuclease purified from Ehrlich ascites tumor cell nuclei and in intact HeLa cell nuclei is irreversibly inactivated by tow concentrations of p-bromo- and p-iodoacetamidophenyl nucleotides and by thymidine-3'-fluorophosphate. Iodoacetate, bromoacetate, and thymidine-5'-fluorophosphate do not affect the enzyme. Although p-haloacetamidophenyl nucleotides inactivate ribonucleic acid polymerase of isolated HeLa cell nuclei, thymidine-3'-fluorophosphate does not affect the activity of this enzyme in vitro. 相似文献
18.
The plaque titer of poliovirus "ribonucleic acid" on monkey kidney cells cultured in vitro is greatly increased by depleting these cells of calcium and treating the "ribonucleic acid" inoculum with a suspension of any one of several poorly water-soluble substances before inoculation. These undissolved substances apparently facilitate infection by serving as solid vehicles for the "ribonucleic acid." 相似文献
19.
橡胶籽是大戟科乔木植物-三叶橡胶的有性繁殖器官,它是褐色并带有银灰色斑纹的椭圆形种子。橡胶籽作为橡胶树的副产物在很长一段时间里只是少量被用来育种其余的均没有被开发利用。橡胶籽仁是一种含油量很高的油料作物,并且粗蛋白含量丰富,含有赖氨酸、组氨酸、缬氨酸、苏氨酸、亮氨酸、苯丙氨酸等必须氨基酸。橡胶籽主要由棕榈酸、亚油酸、亚麻酸、油酸和硬脂酸等成分组成,富含不饱和脂肪酸,营养丰富,具有很高的利用价值。本篇文章将利用ICP-MS等设备对不同品种的橡胶籽中的氨基酸和无机元素进行定性和定量分析,比较不同橡胶籽的氨基酸和无机元素种类与含量差异,并为下一步的研究及橡胶籽产品开发提供理论依据。 相似文献
20.
[目的]对延边黄牛CAPN3基因多态性与氨基酸含量关系进行研究。[方法]应用PCR-SSCP检测了96头延边黄牛CAPN3基因多态性,并采用SPSS软件对各基因型的氨基酸含量进行差异显著性分析。[结果]CAPN3基因发生G55556A突变,差异显著性分析结果显示,该位点不同基因型之间的脂肪酸和氨基酸含量存在差异,其中AA基因型油酸含量显著低于GG基因型（P〈0.05）。不同基因型个体天冬氨酸、谷氨酸、丝氨酸、组氨酸、苏氨酸、精氨酸、丙氨酸、络氨酸、缬氨酸、苯丙氨酸、异亮氨酸、亮氨酸和脯氨酸含量上存在显著性差异,且均表现为AA基因型氨基酸含量显著高于GG基因型。[结论]CAPN3基因与延边黄牛氨基酸含量显著相关。 相似文献