线粒体基因组的变异与哺乳动物高原适应性

青藏高原是世界上最大、最年轻的高原。大气氧分压低、太阳辐射强烈和 气候寒冷等自然特点使得生活在青藏高原上的动物在形态、生态、行为以及生 理机能上都受到深刻的影响，并在进化过程中对高原环境产生了特殊的适应性。 生活在高原上的动物分为世居动物和移居动物，它们处于高原适应过程中的不 同阶段，并且有着不同的高原适应性的特点。为了研究高原哺乳动物所拥有的 特殊高原适应性的遗传基础和进化历史，以及探讨处于不同高原适应阶段的哺 乳动物对高原的适应性在遗传基础上的异同，本研究首次测定和分析了高原世 居动物中的藏羚羊（Pantholops hodgsonii）和高原鼠兔（Ochotona curzoniae） 以及高原移居动物中的藏马（Equns caballus）这三种具有代表性的高原动物的 线粒体全基因组。 1. 藏羚羊线粒体DNA 中的变异及其进化史 在对线粒体上13 个基因进行了进化分析后，我们发现细胞色素氧化酶1 （COX1）基因在藏羚羊和牦牛中都有高的非同义突变的现象。COX1 基因编码 的蛋白是线粒体氧化呼吸链上复合物Ⅳ的一部分，它将电子传递给氧，进行有 氧呼吸并产生能量。考虑到藏羚羊与牦牛都是生活在相同的气候环境中，我们 猜想线粒体基因组编码的COX1 基因的进化可能对青藏高原世居动物适应高原 环境起到作用。藏羚羊的线粒体DNA 数据表明，藏羚羊与绵羊、山羊的亲缘 关系较近，而与羚羊属家族的动物则相对较远，同时我们估算了藏羚羊与绵羊 山羊的分化时间大约为220 万年左右。这一时间与一些学者所估计的青藏高原 隆起时间大致吻合。 2. 高原鼠兔线粒体DNA 中的变异及其进化史 对高原鼠兔线粒体基因组上的基因进行进化分析后发现，对于高原鼠兔这一 分枝上，COX1 基因也有高的非同义突变速率。这表明COX1 基因在高原鼠兔 适应青藏高原高寒缺氧的环境过程中也可能受到选择压力的作用，结合我们在 藏羚羊和牦牛中的分析结果，我们推测高原世居动物在COX1 基因的进化过程 中很多都表现出类似的受选择现象。3. 藏马线粒体DNA 中的变异及其进化史 我们测定了西藏那曲(4500m)、云南中甸(3300m)、云南德钦(3300m)地区共 三匹藏马线粒体全基因组序列。通过对线粒体蛋白编码区的分析发现，与藏羚 羊、高原鼠兔等高原世居动物表现出的COX1 基因受选择不同，在三匹藏马中 NADH6 基因均表现高的非同义突变现象。NDAH6 基因编码的蛋白是线粒体氧 化呼吸链上复合物Ⅰ的一部分，它催化电子从NADH 传递给辅酶Q。不同地区 藏马中NADH6 基因类似的进化方式表明NADH6 基因的进化可能与藏马对高 原极端环境的适应有关。藏马在线粒体基因进化上所表现出的与其它高原世居 动物的不同究竟是由于动物在适应高原的不同阶段其遗传基础和策略的不同所 造成的，还是由于物种间的差异所造成的我们尚不能确定。还需要进一步对高 原动物线粒体基因进行研究。此外，我们对藏马进化史的研究表明藏马可能为 多地区起源

小鲵属分子系统发育研究

小鲵属为亚洲特有的有尾两栖类，是小鲵科之模式属。现记载小鲵属动物有29种，占全科物种数一半以上（Frost, 2007），为小鲵科第一大属。该属分布跨越古北界和东洋界，分布于中国、朝鲜、韩国、日本等地区，其系统学研究一直以来颇为中外学者所关注。澄清该属的物种分类问题，阐明其种间的系统发育关系对整个小鲵科的系统演化与分布格局关系的研究具有关键性意义。 本论文以中国及周边地区的小鲵属物种为主要对象，主要利用分子生物学实验与生物信息学途径相结合的手段，运用支序系统学与分子进化生物学理论及分析方法，展开系统发育的研究。在此基础上诠释现存的分类问题，并探讨该属系统发育关系。 研究材料上，本研究采用野外采集与网络下载数据相结合的方法，获取了较为全面的小鲵属物种DNA序列资料。技术手段上，选取了线粒体DNA的Cytb、12S、16S、NADH 2、COI等多个基因部分片段序列，对小鲵属开展了较为全面系统的研究。分析方法上，针对小鲵属物种各类群的具体情况，运用了处于领域前沿的多种分析方法。应用PAUP、MrBayes、Modeltest、Mega等软件，采用了最大简约法（MP）、邻接法（NJ）、贝叶斯推断（BI）及K2P遗传距离分析等方法。 本研究对小鲵属进行了较为全面的系统发育研究，弥补了有关小鲵属系统发育研究的不足，并得出了以下结果： （1）关于豫南小鲵Hynobius yunanicus的有效性，基于细胞色素b序列的系统发育关系联合形态和染色体组型等证据证明了豫南小鲵是商城肥鲵的同物异名。 （2）获得了较为全面的小鲵属物种系统发育树，并以此解释了北海道滞育小鲵、东北小鲵、中国小鲵与义乌小鲵等存在的分类问题。 （3）本研究利用DNA条形码技术对小鲵属及小鲵科物种进行了鉴定，再次证明豫南小鲵为商城肥鲵的同物异名；并认为猫儿山小鲵与挂榜山小鲵为同物异名。 综上，本研究较为完整地勾勒了小鲵属的系统发育关系全貌，并对小鲵属物种的起源进行了推测。 Hynobius, the type genus of the Family Hynobiidae, is the only exclusively Asian salamander genus. This genus which contains 29 species (beyond half of total Family), is the key group in Hynobiidae. The genus distributed across Palaearctic and Oriental Realm, and was found in China, Korea, and Japan. Systematics of genus Hynobius draws attention of researchers all the times. Resolving the taxonomic and phynogenetic questions of Hynobius is very important to the evolutionary research of Family Hynobiidae. Firstly, studies on systematics of genus Hynobius based on morphology, karyotype and molecular phylogeny of Hynobius are reviewed along with existing questions of this genus. The sequential reaserch project of phylogenetics is perspectively outlined. Using molecular data, we compared Hynobius yunanicus with a sympatric species Pachyhynobius shangchengensis. Our cytb sequences associating with karyotypic and morphological data supportted that H. yunanicus is not a valid species, but a synonym of P. shangchengensis. Because of phenotypic plasticity, some morphological characters are not even suitable for identifying hynobiids. The taxonomy of hynobiids is still controversial to a certain extent (Zhao et al. 1993; Fei, 1999; Chen et al. 2001; Zeng et al. 2006) and needs to be resolved by a new method. Here we examined the utility of COI barcoding for the discrimination of hynobiids. Meantime, the taxonomy of this Family was looked-over again. Our result show that the DNA Barcoding based on COI is easier and more rapidly than classic methods. And the DNA Barcodes data supported the actual taxonomy of Hynobiidae. Based on the achievements of our research, the phylogeny of Hynobius was reconstructed including some new species (H. maoershanensis, H. guabangshanensis, etc). Besides the phylogenetics of Hynobius was outlined, some questions and the hypothesis about the origin of genus Hynobius was put out.

苯并[a]芘对赤子爱胜蚓线粒体编码基因表达影响研究

根据ISO11268-1:1993方法,完成了土壤中苯并[a]芘对赤子爱胜蚓(Eisenia fetida)的人工污染模拟实验.并采用Clontech PCR-SelectTMcDNASubtration Kit构建了污染组和对照组蚯蚓之间的抑制消减文库.经测序和比对分析,在苯并[a]芘诱导上调文库中发现5个线粒体DNA(mtDNA)编码的基因,且在上调文库中具有较高的频率.它们分别为:细胞色素c氧化酶亚基Ⅰ、Ⅱ、Ⅲ,NADH氢脱氢酶亚基1,ATP合成酶亚基.研究表明,土壤中苯并[a]芘污染改变了蚯蚓线粒体基因组的表达水平,线粒体基因组表达异常是多环芳烃污染胁迫的重要分子生物标记物.

Highly ordered mesoporous carbons as electrode material for the construction of electrochemical dehydrogenase- and oxidase-based biosensors

In this work, the excel lent catalytic activity of highly ordered mesoporous carbons (OMCs) to the electrooxidation of nicotinamide adenine dinucleotide (NADH) and hydrogen peroxide (H2O2) was described for the construction of electrochemical alcohol dehydrogenase (ADH) and glucose oxidase (GOD)-based biosensors.

The characteristics of highly ordered mesoporous carbons as electrode material for electrochemical sensing as compared with carbon nanotubes

In this paper, the unique properties of highly ordered mesoporous carbons modified glassy carbon electrode (OMCs/GE) are illustrated from comparison with carbon nanotubes modified glassy carbon electrode (CNTs/GE) for the electrochemical sensing applications.

Characterization and electrocatalytic application of a fullerene/ionic-liquid composite

A fullerene/ionic-liquid composite was explored. Transmission Electron Microscopy (TEM) study showed that in the composite, C-60 mainly exists as nano-clusters, Raman spectrum proved that the composite formed only by physical Mix of C-60 and 1-Butyl-3-methyl-imidazolium hexafluorophosphate (BMIPF6), the combination did not change the chemical naturation of C-60. The electrochemical properties of the composite modified electrode, including the electrode reaction control function and the interfacial potential effect were studied.

Size-controlled synthesis of monodispersed gold nanoparticles stabilized by polyelectrolyte-functionalized ionic liquid

The size-controlled synthesis of monodispersed gold nanoparticles (AuNPs) stabilized by polyelectrolyte-functionalized ionic liquid (PFIL) is described. The resulting AuNPs' size, with a narrow distribution, can be tuned by the concentration of HAuCl4. Such PFIL-stabilized AuNPs (PFIL-AuNPs) showed a high stability in water at room temperature for at least one month; they were also quite stable in solutions of pH 7-13 and high concentration of NaCl.

Electrochemical Sensing and Biosensing Platform Based on Chemically Reduced Graphene Oxide

In this paper, the characterization and application of a chemically reduced graphene oxide modified glassy carbon (CR-GO/GC) electrode, a novel electrode system, for the preparation of electrochemical sensing and biosensing platform are proposed. Different kinds of important inorganic and organic electroactive compounds (i.e., probe molecule (potassium ferricyanide), free bases of DNA (guanine (G), adenine (A), thymine (T), and cytosine (C)), oxidase/dehydrogenase-related molecules (hydrogen peroxide (H2O2/beta-nicotinamide adenine dinucleotide (NADH)), neurotransmitters (dopamine (DA)), and other biological molecules (ascorbic acid (AA), uric acid (UA), and acetaminophen (APAP)) were employed to study their electrochemical responses at the CR-GO/GC electrode, which shows more favorable electron transfer kinetics than graphite modified glassy carbon (graphite/GC) and glassy carbon (GC) electrodes.

Highly ordered mesoporous carbons-based glucose/O-2 biofuel cell

This study demonstrates a novel compartment-less glucose/O-2 biofuel cell (BFC) based on highly ordered mesoporous carbons (OMCs) with three-dimensionally (3D) interconnected and ordered pore structures. OMCs are used as supports for both stably confining the electrocatalyst (i.e., meldola's blue, MDB) for NADH oxidation and the anodic biocatalyst (i.e., NAD(+)-dependent glucose dehydrogenase, GDH) for glucose oxidation, and for facilitating direct electrochemistry of the cathodic biocatalyst (i.e., laccase, LAC) for O-2 electroreduction. In 0.10 M pH 6.0 PBS containing 20 mM NAD(+) and 60 mM glucose under the air-saturated atmosphere, the open circuit voltage (0.82 V) and the maximum power output (38.7 mu W cm(-2) (at 0.54V)) of the assembled compartment-less OMCs-based BFC are both higher than those of carbon nanotubes (CNTs)-based BFC (0.75 V and 2.1 mu W cm(-2) (at 0.46 V)).

Photoinduced DNA Cleavage by alpha-, beta-, and gamma-Cyclodextrin-Bicapped C-60 Supramolecular Complexes

Water-soluble supramolecular inclusion complexes of alpha-, beta-, and gamma-cyclodextrin-bicapped C-60 (CD/C-60) have been investigated for their photoinduced DNA cleavage activities, with the aim to assess the potential health risks of this class of compounds and to understand the effect of host cyclodextrins having different cavity dimensions. Factors such as incubation temperature, irradiation time, and concentration of NADH or CDs/C-60 supramolecular inclusion complexes have been examined. The results show that alpha-, beta-, and gamma-CDs/C-60 are all able to cleave double-stranded DNA under visible light irradiation in the presence of NADH. However, a difference in the photoinduced DNA cleavage efficiency is observed, where the cleavage efficiency increases in the order of alpha-, beta-, and gamma-CD/C-60. The difference is attributed to the different aggregation behavior of the inclusion complexes in aqueous solution, which is correlated to the cavity dimension of the host cyclodextrin molecules.

Preparation and layer-by-layer self-assembly of positively charged multiwall carbon nanotubes

The report described a method of more stably dispersing oxidized carbon nanotubes (CNTs) by forming complex with polycation and the layer-by-layer self-assembly behavior of the complex with polyanion was studied. The properties of the self-assembled multilayer film containing carbon nanotubes were studied. Cyclic voltammetry, UV-vis-NIR spectroscopy, electrochemical impedance spectroscopy and scanning electron microscopy were used for characterization of film assembly. UV-vis-NIR spectroscopy and cyclic voltammetry study indicated the uniform growth of the film. Electrochemical impedance spectroscopy results showed that incorporating of carbon nanotubes in the polyelectrolyte multilayers; decreased in the electron-transfer resistance R, indicating more favorable electrochemical reaction interface. The electrocatalytic property of the multilayer modified electrode to NADH was investigated mainly with different numbers of the bilayers; and the results showed that along with the increase of the assembled bilayers the overpotential of NADH oxidation decreased. The detection lit-nit Could reach 6 mu M at a detection potential of 0.4 V.

新法制备铁氰化钴修饰玻碳电极及多巴胺的电催化氧化

过渡金属铁氰化物由于可用于电催化、离子选择性电极以及固态电池和电致变色装置的材料等而受到关注[1 ] 。铁氰化钴 (CoHCF)由于性能优越 ,常被作为模型化合物加以研究[2 ] ,如Kulesza等[3] 利用电化学石英晶体微天平和X光吸收光谱技术研究了它的结构 ,Sato等[4] 对其表现出的磁性进行了研究 ,我们曾报道过CoHCF修饰电极催化NADH和抗坏血酸的氧化[5,6] 等。用电化学制备CoHCF修饰电极的方法可分为 2种 ,一种是电化学共沉积法 ,另一种是所谓的“新生金属法”。电化学共沉积法是将电极放在含有Co2 +盐和K3Fe(CN) 6的溶液中于一定电位范围内循环扫描。由于Co2 +盐和K3Fe(CN) 6存在同一溶液中 ,所以它们的浓度不宜太高 ,一般控制在 0 5～ 1 0mmol/L范围内。若浓度太高 ,就会在溶液中发生化学沉积使溶液变浑浊。如浓度较低 ,要得到较厚的CoHCF膜 ,循环次数必须很多 ,耗时较长。“新生金属法”是先在Co2 +盐溶液中 ,控制电极电位使Co2 +被还原成Co沉积在电极表面 ,然后将电极转入K3Fe(CN) 6溶液中进行电位扫描 ,从而在电极表面沉积C...

Carbon ceramic electrodes modified with sub-micron particles of new methylene blue (NMB) intercalated alpha-zirconium phosphate

New methylene blue-intercalated a-zirconium phosphate (NMBZrP) was synthesized in the presence of n-butylamine and characterized by powder XRD, FTIR, TEM and elemental analysis. Sub-micron particles of NMBZrP in deionized water were apt to deposit onto the surface of graphite powder to yield graphite powder-supported NMBZrP, which was subsequently dispersed into methyltrimethoxysilane-derived gels to fabricate surface-renewable, stable, rigid carbon ceramic electrodes containing new methylene blue. Cyclic voltammetric studies revealed that peak currents of the NMBZrP-modified electrode were surface-confined at low scan rates but diffusion-controlled. at high scan rates. In addition, NMBZrP immobilized in a carbon ceramic matrix presented a two-electron, three-proton redox process in acidic aqueous solution in the pH range from 0.52 to 3.95.

Sol-gel derived carbon ceramic electrode bulk-modified with tris(1,10-phenanthroline-5,6-dione)iron(II) hexafluorophosphate and its use as an amperometric iodate sensor

A surface-renewable tris (1,10-phenanthroline-5, 6-dione) iron (II) hexafluorophosphate (FePD) modified carbon ceramic electrode was constructed by dispersing FePD and graphite powder in methyltrimethoxysilane (MTMOS) based gels. The FePD-modified electrode presented pH dependent voltammetric behavior, and its peak currents were diffusion-controlled in 0.1 mol/L Na2SO4 + H2SO4 solution (pH = 0. 4). In the, presence of iodate, clear electrocatalytic reduction waves were observed and thus the chemically modified electrode was used as an amperometric sensor for iodate in common salt. The linear range, sensitivity, detection limit and response time of the iodate sensor were 5 x 10(-6)-1 x 10(-2) mol/L, 7.448 muA.L/mmol, 1.2 x 10(-6) mol/L and 5 s, respectively. A distinct advantage of this sensor is its good reproducibility of surface-renewal by simple mechanical polishing.

Electrochemiluminescence of tris(2,2 '-bipyridine)ruthenium(II) immobilized in poly(p-styrenesulfonate)-silica-Triton X-100 composite thin-films

The electrochemiluminescence (ECL) of tris(2,2'-bipyridine)ruthenium(ii) [Ru(bpy)(3)(2+)] immobilized in poly(p-styrenesulfonate) (PSS)-silica-Triton X-100 composite films was investigated. The cooperative action of PSS, sol-gel and Triton X-100 attached Ru(bpy)(3)(2+) to the electrode strongly, and the presence of Triton X-100 prevented drying fractures of the sol-gel films during gelation and even on repeated wet-dry cycles. The modified electrode was used for the ECL detection of oxalate, tripropylamine (TPA) and NADH in a flow injection analysis (FIA) system with a newly designed flow cell. The detection scheme exhibited good stability, short response time and high sensitivity. Detection limits were 0.1, 0.1 and 0.5 mu mol L-1 for oxalate, TPA and NADH, respectively, and the linear concentration range extended from 0.001 to 1 mmol L-1 for the three analytes. Applications of the flow cell in ECL and electrochemical detection, as well as the immobilization of reagents based on the cooperative action, are suggested.