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1.
RAPD标记在山葡萄种质鉴定中的应用   总被引:4,自引:1,他引:4  
王军  葛玉香  贺普超 《植物研究》2004,24(4):473-476
采用修改后的CTAB 法获得了高质量的基因组DNA 。利用RAPD 标记技术对山葡萄7 份种质进行鉴定, 用4 个引物(从30 个引物中筛选)对试材进行PCR 扩增, 共扩增出30 条谱带, 平均每条引物产生7.5 条谱带, 其中21 条谱带为多态性谱带, 占总谱带数的70%。不同引物扩增的谱带数不同, 范围在6~9 条之间。利用4 个引物扩增出的多态性谱带可以将7 份山葡萄种质区分。  相似文献   

2.
膜翅目昆虫酯酶同工酶的比较研究   总被引:33,自引:3,他引:33  
用聚丙烯酰胺凝胶等电聚焦电泳分析了膜翅目七个总科、蜜蜂总科9个属, 蜜蜂属6个种和西方蜜蜂4个宗样品的酯酶同工酶.总科代表之间酶谱的差别大于总科内各属间的差别;各属间的酶谱也有显著差别;而属内各种间的酶谱比较接近, 但每个种都有自己特有的谱型, 彼此易于区分.没有发现宗间有明显差别.本文还在实验的基础上讨论了用电泳酶谱方法作为昆虫分子分类学研究手段的可行性.  相似文献   

3.
本研究采用聚丙烯酰胺凝胶电泳法,分析了樱亚科8个种共17个生物型枝皮、叶片的过氧化物同工酶(POD),初步确定了各样品枝皮、叶片的POD同工酶酶谱特征.根据酶谱相似系数对样品进行了Fuzzy聚类分析.通过样品酶谱积值的F检验,选定了樱亚科植物分属的最佳阈值,为同工酶谱聚类效果研究提供新方法.  相似文献   

4.
水生生物粒径谱/生物量谱研究进展   总被引:7,自引:0,他引:7  
周林滨  谭烨辉  黄良民  连喜平 《生态学报》2010,30(12):3319-3333
介绍了水生生物粒径谱概念,粒径谱理论的提出背景及其发展历程。综述了浮游生物、底栖生物、微型生物和鱼类粒径谱的研究现状;并以粒径谱理论在鱼类潜在产量估算方面的应用为重点,介绍了粒径谱理论的应用。回顾了国内生物粒径谱研究现状;结合新陈代谢理论、宏生态学与粒径谱理论的联系,新的粒径测量手段的应用,传统分类方法与粒径方法的关系,以及粒径谱模型研究的特点,展望未来粒径谱研究的前景。认为粒径谱研究已经历了半个多世纪的发展和多个领域的应用,给人们以区别于传统物种分类的崭新视角,成为生态学研究,尤其是水生生态学研究的热点。目前水生生物包括浮游生物、底栖生物、微型生物和鱼类粒径谱/生物量谱的分析方法、模型和理论研究已取得了一些进展,但由于各类生物个体形态、结构呈现多样化,数据获取的难度以及其他各种因素影响,使得研究工作发展缓慢,海洋生物粒径谱研究尤其困难。随着海洋生物资源评估、利用与渔业生态系统管理的需要,应重视加强粒径谱/生物量谱的研究,包括不同类型生物的粒径分布曲线、捕食与被捕食之间的关系、新陈代谢特征、时空尺度变异、粒径谱模型的假设条件和新模型的建立,以及先进测量技术应用等,这将是今后粒径谱/生物量谱研究需要引起关注的重点内容。  相似文献   

5.
AFLP在芒果品种鉴定中的应用   总被引:26,自引:1,他引:25  
房经贵  乔玉山  章镇 《广西植物》2001,21(3):281-283,286
利用 AFLP分子标记技术对 1 6个芒果 (Mangif era indica L.)品种以及 7个芒果砧木材料进行了初步研究 ,6对 AFLP选择性引物共产生 2 0 4条清晰谱带。同时利用品种间共有谱带率 (Band-sharing)对某些品种间的遗传关系进行了分析。 1 6个栽培品种间的平均共有谱带率为 83 % ,变异幅度为 70 %~ 94% ,7个砧木间的平均共有谱带率则为 80 % ,变异幅度为 5 3 %~ 96%。  相似文献   

6.
蜡梅17个品种过氧化物同工酶的研究   总被引:14,自引:0,他引:14  
陈志秀 《植物研究》1995,15(3):403-411
采用聚丙烯酰胺凝胶电泳系统,多次进行了蜡梅17个品种的过氧化物同工酶测定。测定结果发现:蜡梅酶谱具有多态特性;蜡梅品种间酶谱差异显著,每个品种均有其特征酶谱,或以其酶带数目、Ff及活性强弱、酶带宽度与其它品种相区别。同时,采用"排序方法"和聚类分析,对蜡酶17个品种酶谱的相似程度进行了研究。研究结果表明,两种方法研究蜡梅品种的酶谱,均可达到定量比较水平,避免单一酶谱谱带确定蜡梅品种的偏阳性,为其品种鉴定与检验提供了新的依据和手段。同时,还表明,聚类分析进行的蜡梅品种酶谱聚类结果,与其形态分类相一致,但与其品种群划分不相吻合,其原因可能与蜡梅品种起源的复杂性和多源性所引起。  相似文献   

7.
秦艽中的环烯醚萜甙成分   总被引:22,自引:0,他引:22  
秦艽为著名传统中药。中青海西宁产秦艽的甲醇提取物的水溶性部分分离到1个新裂环烯醚萜甙,命名为秦艽甙A,2个已知的环烯醚萜甙即龙胆苦甙和哈马甙以及2个甾醇甙,胡萝卜甙和β-谷甾醇-3-O-龙胆糖甙。这些化合物的结构通过红外光谱、紫外光谱、核磁共振波谱(包括-维氢醇-3-O-龙胆糖甙。这些化合牧的结构通过红外光谱、紫外光谱、核磁共振波谱(包括一维氢谱、碳谱、氢-氢相关谱、碳-氢相关谱、远程碳-氢相关谱  相似文献   

8.
梁涛  杜振华  黄慧宇 《遗传》1990,12(5):1-3
以普通小麦为遗传背景,分别附加了天蓝冰草1个染色体组中的1条染色体的7个异附加系为材料,采用薄层聚丙烯酰胺凝胶等电聚焦电泳技术,对各异附加系进行了酯酶、过氧化物酶和乙醇脱氢酶的同工酶酶谱带分析,找到了5个异附加系的特征谱带。通过异附加系间的酶谱带差异比较,可将所有异附加系鉴别出来。为今后鉴别异附加系提供了一个快速、简便的方法。  相似文献   

9.
柏木属植物过氧化物酶同工酶的研究   总被引:9,自引:0,他引:9  
江洪  王琳 《植物分类学报》1986,24(4):253-259
用聚丙烯酰胺凝胶电泳分析了柏木属9个种的过氧化物酶同工酶。结果表明:属内种 间具有明显的酶谱差异,每个种都有其特征酶谱。并用排序的方法对柏木属9个种酶谱的相 似程度进行了研究,据酶谱的排序结果把9个种分为5个类群。其中:巨柏、西藏柏木、干香 柏、岷江柏木和剑阁柏木为一类群; 地中海柏木、柏木、墨西哥柏木和绿干柏各为一类群,从分 子水平上论证了前人对于柏木属各种间亲缘关系的论述。研究结果还表明,柏木属植物近缘 种间过氧化物酶同工酶谱相似程度的替代与近缘种间的地理替代表现出强烈的映射关系,这 种关系可以用来揭示植物地理替代的规律。柏木属内种间平均酶谱距离为0.75,推测其地质 发生年代为侏罗纪。本文还发现用排序的方法研究同工酶谱可以达到定量比较的水平,在实践中有较多的优越性。  相似文献   

10.
利用RAPD标记分析东亚地区桔梗的亲缘关系   总被引:5,自引:0,他引:5  
严一字  吴基日 《植物研究》2007,27(3):308-312
对取自中国、日本、韩国和朝鲜等东亚地区的24个桔梗种质资源,利用RAPD-PCR标记方法,分析了其遗传变异和遗传关系,旨在为桔梗的品种鉴定和杂交育种的亲本选择提供理论依据。结果表明: (1)用11个引物扩增出131条谱带,平均每个引物扩增出11.9条谱带,并扩增出61个多态性谱带,平均每个引物扩增出5.5条多态性谱带,显示出了相对高的多态率(46.6%)。(2)得到的RAPD数据的遗传相似性范围为0.668~0.994,并以遗传相似系数0.78为标准,将24个桔梗种质资源分为7个类群。  相似文献   

11.
The computer program casper uses (1)H and (13)C NMR chemical shift data of mono- to trisaccharides for the prediction of chemical shifts of oligo- and polysaccharides. In order to improve the quality of these predictions the (1)H and (13)C, as well as (31)P when applicable, NMR chemical shifts of 30 mono-, di-, and trisaccharides were assigned. The reducing sugars gave two distinct sets of NMR resonances due to the α- and β-anomeric forms. In total 35 (1)H and (13)C NMR chemical shift data sets were obtained from the oligosaccharides. One- and two-dimensional NMR experiments were used for the chemical shift assignments and special techniques were employed in some cases such as 2D (1)H,(13)C-HSQC Hadamard Transform methodology which was acquired approximately 45 times faster than a regular t(1) incremented (1)H,(13)C-HSQC experiment and a 1D (1)H,(1)H-CSSF-TOCSY experiment which was able to distinguish spin-systems in which the target protons were only 3.3Hz apart. The (1)H NMR chemical shifts were subsequently refined using total line-shape analysis with the PERCH NMR software. The acquired NMR data were then utilized in the casper program (http://www.casper.organ.su.se/casper/) for NMR chemical shift predictions of the O-antigen polysaccharides from Klebsiella O5, Shigella flexneri serotype X, and Salmonella arizonae O62. The data were compared to experimental data of the polysaccharides from the two former strains and the lipopolysaccharide of the latter strain showing excellent agreement between predicted and experimental (1)H and (13)C NMR chemical shifts.  相似文献   

12.
Two compounds identified as 7,7-dimethyl-2-methylenebicyclo[3.1.1]heptan-6-ol acetate and 6,6,8,9-tetramethyltricyclo[3.3.3.0]undec-7-en-2-ol were isolated from the essential oil of the fresh leaves of Psiadia anchusifolia. Their structures were determined by extensive NMR studies (1H NMR, 13C NMR, DEPT, 1H-1H COSY, HSQC, HMBC) as well as by X-ray crystallographic analysis.  相似文献   

13.
High-resolution 1H NMR spectroscopy as a complementary method in the analysis of human bone marrow fatty acid (FA) composition was examined. Marrow FA composition in 10 bone samples measured by NMR and gas chromatography (GC) were compared. NMR T1 relaxation time of FA was determined and reproducibility tests were performed to assess the variability. Good correlations were obtained between the NMR and GC results for omega-6 polyunsaturated fatty acid (PUFA) (Spearman r, 0.878), omega-3 PUFA (0.895), monounsaturated FA (0.964) and saturated FA (0.939). The NMR method tended to overestimate saturated FA and underestimate omega-3/omega-6 ratio compared to GC results. T1 relaxation time of marrow FA was 0.56-3.65s. Coefficient of variation of the NMR method was 0.6-8.2% in intra-experimental and 0.2-8.4% in inter-experimental measurements. This study demonstrates a complementary role for 1H NMR spectroscopy as an additional analytical tool in human lipid research.  相似文献   

14.
Molecular replacement (MR) is widely used for addressing the phase problem in X-ray crystallography. Historically, crystallographers have had limited success using NMR structures as MR search models. Here, we report a comprehensive investigation of the utility of protein NMR ensembles as MR search models, using data for 25 pairs of X-ray and NMR structures solved and refined using modern NMR methods. Starting from NMR ensembles prepared by an improved protocol, FindCore, correct MR solutions were obtained for 22 targets. Based on these solutions, automatic model rebuilding could be done successfully. Rosetta refinement of NMR structures provided MR solutions for another two proteins. We also demonstrate that such properly prepared NMR ensembles and X-ray crystal structures have similar performance when used as MR search models for homologous structures, particularly for targets with sequence identity >40%.  相似文献   

15.
In the present work we have investigated the macromolecules that contribute to the brain 1H NMR spectrum. The cerebral cortex showed distinct resonances at the uncrowded methyl- and methylene chemical shift scale of the spin-echo 1H NMR spectrum. The peaks at 1.22 and 1.40 ppm (relative to the methyl protons of N-acetyl aspartate at 2.02 ppm) arise from cerebral macromolecules without evidence for co-resonances from low molecular weight metabolites as shown by the spin-spin relaxation decays of these resonances. In addition to these NMR signals, peaks at 0.9 and 1.7 ppm from macromolecules were detected. These resonances are from proteins, and we have identified the polypeptides that contributed to the 1H NMR peaks. Two proteins that were present at concentrations of 250 and 350 micrograms/g of dryed tissue showed 1H NMR spectra that resembled the macromolecular pattern in the cerebral 1H NMR spectrum. They were identified as thymosin beta 4 and histone H1, respectively. Thymosin beta 4 was present in soluble high speed cytoplasmic fraction and in P2 pellet, whereas histone H1 was detected in nuclear enriched fraction. A chemical shift-correlated two-dimensional 1H NMR spectrum of thymosin beta 4 in vitro revealed a coupling pattern that matched the macromolecule in the cerebral cortex which we have previously noted (Kauppinen R. A., Kokko, H., and Williams, S. R. (1992) J. Neurochem. 58, 967-974). On the basis of both one- and two-dimensional NMR evidence, subcellular distribution and high concentration, we assign the 1H NMR signals at 0.9, 1.22, 1.40, and 1.7 ppm in the cerebral cortex to thymosin beta 4.  相似文献   

16.
Lee S  Jung S 《Carbohydrate research》2002,337(19):1785-1789
Cyclosophoraoses (cyclic-(1-->2)-beta-D-glucans) produced by Rhizobium meliloti were used as a novel chiral NMR solvating agent. 13C NMR spectroscopic analysis as an enantiodiscriminating tool was carried out where NMR signal splittings were observed on the interactions of cyclosophoraoses with the enantiomers of N-acetylphenylalanine, catechin and propranolol. The 13C chemical shifts of cyclosophoraoses induced by the enantiomeric interactions predominantly occurred at the C-1 and C-2 carbons associated with the -glycosidic linkage.  相似文献   

17.
A high-field NMR study of the polysaccharidic fraction extracted from Lentinula edodes mycelium grown on olive mill waste waters is reported. Diffusion-ordered NMR spectroscopy (DOSY) was applied to the polysaccharidic fraction. The results showed the presence of two polysaccharides of different sizes, whose structures were revealed using one- and two-dimensional NMR techniques. These two polysaccharides were identified as xylan and lentinan.  相似文献   

18.
The structure of human protein HSPC034 has been determined by both solution nuclear magnetic resonance (NMR) spectroscopy and X-ray crystallography. Refinement of the NMR structure ensemble, using a Rosetta protocol in the absence of NMR restraints, resulted in significant improvements not only in structure quality, but also in molecular replacement (MR) performance with the raw X-ray diffraction data using MOLREP and Phaser. This method has recently been shown to be generally applicable with improved MR performance demonstrated for eight NMR structures refined using Rosetta (Qian et al., Nature 2007;450:259-264). Additionally, NMR structures of HSPC034 calculated by standard methods that include NMR restraints have improvements in the RMSD to the crystal structure and MR performance in the order DYANA, CYANA, XPLOR-NIH, and CNS with explicit water refinement (CNSw). Further Rosetta refinement of the CNSw structures, perhaps due to more thorough conformational sampling and/or a superior force field, was capable of finding alternative low energy protein conformations that were equally consistent with the NMR data according to the Recall, Precision, and F-measure (RPF) scores. On further examination, the additional MR-performance shortfall for NMR refined structures as compared with the X-ray structure were attributed, in part, to crystal-packing effects, real structural differences, and inferior hydrogen bonding in the NMR structures. A good correlation between a decrease in the number of buried unsatisfied hydrogen-bond donors and improved MR performance demonstrates the importance of hydrogen-bond terms in the force field for improving NMR structures. The superior hydrogen-bond network in Rosetta-refined structures demonstrates that correct identification of hydrogen bonds should be a critical goal of NMR structure refinement. Inclusion of nonbivalent hydrogen bonds identified from Rosetta structures as additional restraints in the structure calculation results in NMR structures with improved MR performance.  相似文献   

19.
39K nuclear magnetic resonance (NMR) spectra were readily obtained, in vivo, from rat muscle, kidney, and brain in 5-10 min with signal-to-noise ratios of approximately 20:1. Quantitation of the K+ signal was achieved by reference to an external standard of KCl/dysprosium nitrate as well as by reference to the proton signal from tissue water. In vitro NMR studies of isolated tissue showed a K+ visibility (NMR K+/total tissue K+) of 96%, 62 +/- 8%, 47 +/- 1.9%, 45 +/- 3.5%, and 43 +/- 2.5% for blood, brain, muscle, kidney, and liver, respectively. Absolute tissue K+ was determined by flame photometry of acid-digested tissue. Changes in tissue K+ status by chronic K+ depletion or acute K+ loading produced changes of 39K NMR signal intensity that were equal to changes of absolute tissue K+. Acidosis, alkalosis, mannitol, or RbCl infusion did not significantly change the NMR K+ signal. These results indicate that the changes in K+ detected by NMR were specifically and accurately detected. To investigate the factors that affect the 39K NMR signal, the effects of liver homogenate on 39K NMR signal intensity were studied. Addition of homogenate produced a 60% loss of signal intensity, suggesting that a large portion of cell K+ may be only 40% visible. Addition of RbCl to undiluted homogenate increased the NMR K+ signal by 11 +/- 2 mumol/g. Addition of H2O or NaCl had no effect, suggesting that Rb+ was replacing K+ in sites of low (less than 40%) NMR visibility. These results demonstrate that 39K NMR experiments can be performed using intact organs.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

20.
利用柱色谱从异柱五加 (Acanthopanax sieboldianus forma albeofolium Yook) 叶的甲醇提取液中分离出四个齐墩果烷型皂苷类化合物.通过波谱方法(1H NMR、13C NMR、2D NMR和FAB-MS)鉴定它们分别为kalopanax-saponin B (1)、acanthopanax saponin CP3(2)、kalopanax-saponin A (3) 和sieboldianoside A (4).  相似文献   

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