973 resultados para B ... n C ... f.
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蛇毒金属蛋白酶(SVMPs) 型成员的家族，它们在结构上表现出较大的多样性，有的蛇毒金属蛋白酶除了含有酶结 构以外在羧基端还添加了更多的结构，如：去整合素样结构域、富含半胱氨酸结构域、 外源凝集素结构域，这种结构多样性导致了蛇毒金属蛋白酶生物活性上的多样性。眼镜 蛇科中的蛇毒主要以神经毒为主，对其金属蛋白酶成分的研究比较少，本文以眼镜王蛇 蛇毒中的金属蛋白酶为研究对象，探讨了它的生物活性、结构特点, 毒金属蛋白酶结构与功能的关系提供了新的研究信息。 首先，通过分子筛凝胶过滤、阴离子交换和肝素亲合层析，我们从梧州产眼镜王 蛇(Ophiophagus hannah)55,000Da 了其N SQKKDFLEEKKYLELYIVADYVMFR，与其它蛇毒金属蛋白酶的N 序列相似性较高，命名为Ohagin。接下来我们研究了该蛋白对纤维蛋白原的作用，发 现Ohagin α-EDTA 完全抑制， 但不被PMSF Ohagin 能抑制TMVA 板聚集，并且这种抑制效应是剂量依赖性的。我们通过cDNA 指纹图谱方法确定了Ohagin Ohagin cDNA 611 长度的开放阅读框，包括信号肽、前肽和成熟蛋白所含有的金属蛋白酶结构域、去整合 素样结构域以及富含半胱氨酸结构域，根据这一结构特点，把Ohagin P-III 金属蛋白酶。将Ohagin P-Ⅲ型蛇毒金属蛋白酶家族中有代表性的22 种 毒素蛋白序列进行比对和进化树分析后发现Ohagin P-Ⅲa P-b 型和P-c 的蛇毒金属蛋白酶的亲缘关系较远，而与眼镜蛇科已知的几种金属蛋白酶亲缘关系较 近，推测它们的生物活性也类似，有可能属于新的P-III 型蛇毒金属蛋白酶亚家族。
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本工作用线粒体细胞色素b基因全序列探讨了白腹鼠属（NiviventerMus musculus 在白腹鼠属的分子系统发育研究中，本研究首次对来自青藏高原东南部和台湾的932个个体的细胞色素b全序列进行了测定和分析。用最大简约法、最大似然法和贝叶斯法三种构树方法构出的进化树一致表明，93DNAA包括社鼠、台湾社鼠、台湾白腹鼠、刺毛鼠、梵鼠和灰腹鼠6B2种；系CDNA1.2-0.13百万年）的社鼠化石为依据推算该属的分歧时间。结果表明该属的起源于1.64AB分化发生在1.461.29-0.67 在小家鼠的分子系统地理学研究中，通过测定来自中国12184Genbank里的单倍型，首次研究小家鼠在中国的分子系统地理格局、种群历史和生物地理过程。184个样品定义了660.95，核苷酸多样性为0.01266Genbank62DNADNA84.03%DNADNA16 60022 00011 00020 00040 0006 700）年前。依据单倍型和核苷酸的多样性、单倍型进化网络关系以及单倍型歧点分布图综合推断小家鼠在中国的两个系在末冰期时经历了快速的种群扩张导致今天的地理分布格局。根据系统发育树的结果推断，北方系种群的大体扩散方向是从北往南，而南方系是从南往北迁移。小家鼠以长江为界分为南方系和北方系的系统地理模式、扩散方向和种群的扩散时间与人以长江为界分为南方人和北方人、扩散方向、扩散时间（60 000－16 000）基本一致，这可能暗示人类活动对小家鼠的迁移产生的重要影响。
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裂腹鱼类起源鳃亚科鱼类的观点得到了多数学者的支持。但是，鱼巴亚科鱼类是一个非常庞杂的类群，裂腹鱼类究竟起源于鳃亚科的哪一个小类群或裂腹鱼类与哪个小类群更为接近？这样的小类群又怎样随着急剧隆起的青藏高原峥演化发展成为现今的裂腹鱼类？不同的学者从不同的研究领域出发，得出了较为不一致甚至是相互对立的结论。裂腹鱼类（我国有1176rCO3Lztciocyprinus2Sinocyclocheilus）的26small-scaledbarbids）。为了探讨细鳞鱼巴类和裂腹鱼类的系统发育关界本文应用分支系统学的方法和原理，选择小裂腹鱼SRparvusP.c.chunglienensisGp.potaniniL.langsoniP.pingiregani、抚仙金线鱼巴saB．baoshanensisC.auratusC．(C)chilia作为外类群，用来对裂腹鱼类和细鳞鳃类进行性状的极化和系统发育分析。通过对122463个性状进行描述和比较，并构建了供系统发育分析的特征矩阵。应用PAUPl1。根；第一椎体横突退化等特征外，还有镖的前后比例、前鳄骨的特征、尾舌骨的形状，基枕骨的骨质盘特征等诸多特征存在着显著差异。支持了陈湘舞等（198413419812000）。裂腹鱼类和似鳃、妒鲤的起源时间可能稍晚一些。可以设想，第三纪末期的鳃亚科鱼类物种分化不是很多，相互之间的亲缘关系较近，分布于'33个代表种都聚在一起，其内部关系和与其他种的关系都较为稳定，为鳃亚科鱼类中较为特化的一支。与陈湘舞等（198419814）似媳和妒鲤之间的亲缘关系最近，它们很可能起源于最近的共同祖先。尽管二者作为一个单系的支持率并不是很高（大于506015：）裂腹鱼类与妒鲤＋似鳃的系统关系最近，这意味着裂腹鱼类和妒鲤＋似鳃有最近的共同祖先或它们之间的关系较它们与金线鳃鱼类的关系更ae7）通过国内外鱼类学者对鲤科鱼类和纪亚科鱼类各分类单元定义的比较，结合本文的研究结果，认为国外学者的一些分类系统仍然存在一些尚待解决的问题，故建议目前暂不宜将之引入到我国的鱼类分类系统中。
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精子从男性生殖道释放后必须经过获能和顶体反应，才能与卵子结合。获能和顶体反应后，精子细胞内和精子表面的许多大分子都会发生改变。利用这些变化，可探索新的避孕方法和男性不育诊断及治疗的新途径。本文将正常人精子于体外在BWWBSAA2318750AR sperm）作为抗复，腹腔免疫Balb/CNT spermELISA法检测所得杂交瘤细胞分泌的抗体，得到了近百株阳性杂交瘤，其中已克隆并得到腹水的有23U937，RajiJurkatNT和ARSASI）试验；免疫印迹测定单抗相应抗原的分子量。主要结果如下：1.NTAR精子反应的ELISA12AR精子抗原发生反应（A6NTB5个则与这两种精子抗原都呈阳性反应（C2.在得到的2321IgMIgC_1和IgG_(2a)3.23个单抗与白细胞系的交叉反应强度不同。ABC组单抗则呈现要么很强、要么很弱的交叉反应。4.NT sperm, AR spermARNT精子。5.9个单抗显示较强的精子凝集作用，另有96.免疫印迹结果表明，有916－146kDa，其余1410WHOWHO
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制备了3AITOSiO2／Alq3Al，B：ITO／Alq3SiO2AlCITOSiO2／Alq3SiO2AlAB，在正向偏压（ITO接正极）下才能观察到发光；而对于器件CBC产生的蓝色发光相对绿光逐渐增强。这主要是由于SiO2Alq3A，在反向偏压下被热电子碰撞激发出的空穴与正向偏压下从Al
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于2010-11-23
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保水剂是一种化学节水材料，它的应用是农林业生产中抗旱节水的一项高新技术。但是保水剂的成本一直据高不下，生产工艺复杂，性能不理想。本文通过水溶液聚合法采用简化工艺对单体与接枝聚合母体材料进行接枝聚合，研制新型高吸水树脂。 8:10.15%；引发剂用量为单体用量的0.03%90%655B>E>C>A>D
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三面压缩式高超声速进气道在侧压式进气道的基础上加入顶面压缩，理论上具有的更短的压缩距离，从而有利于超声速飞行器的整体设计。该进气道不同于传统的顶压式进气道和侧压式进气道，由于其压缩激波在竖直和水平方向都存在，因此出现三维空间的激波相交和反射，造成流场复杂度大大增加，而其也直接影响了进气道设计构型与波系的相对位置关系及进气道性能。\newline 三面压缩进气道由于顶板与侧板两个方向压缩，在顶板与侧板相交线附近区域，激波并不是简单的二维平面激波结构。顶压激波和侧压激波相交后，在波型上产生了明显的变化。在角区的激波相干后的波系结构：顶板激波与侧壁激波相交后，都变得不再连续，即在相互"""断裂"2,对进气道性能的影响以及如何规划三面压缩进气道设计构型都还需要深入的探索。忽略激波边界层干扰，专注于激波相干现象本身，对于这种三维激波相干结构开展了无黏数值分析研究，探索了其关键影响因素，理论分析了其相干特征。\newline 本文分析认为角区波系可分成$A$，$B$，$C$，$D$，$E$5$A$$B$3$C$1压缩的区域；$D$为经过顶压激波31$E$2压缩的区域。对于顶压激波来说，$B$区域的气体与$D$区域的气体参数并不相同，因为$D$区域的气体还经过了侧压激波的压缩，因此在相同的气流转角下，$D$区域的顶板激波角大于$B$区域的顶板激波角，所以顶压激波在穿越侧压激波后发生了""7的位置高于34"断裂"\newline
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本学位论文共有5 在第1Paeonia lactiflora Pall.14个化合物，其中12-I15株厌氧菌中筛选出10Lactobacillus brevis AS1.12 在第2Saussurea involucrate Kar.et Kir.MS、NMR等波谱解析，共分离鉴定了282个新倍半萜化合物的结构分别表征为6α-6-β-D-11βH-11,13-8α-O-(6-)-β-D-吡喃葡萄糖苷。 第3Zanthoxylum nitidum （Roxb.DC.MS、NMR等波谱解析以及X-162 第4Marsdenia tenacissima (Roxb.) Wight et Arn.MS、NMR等波谱解析以及X-14C214tenacigenoside A, tenacigenoside B, tenacigenoside C和tenacigenoside D3-O-6-deoxy-3-O-methyl-β-D-allopyranosyl-(1→4)-β-D-oleandropyranosyl-17β-tenacigenin B (62), 3-O-2,6- dideoxy-4-O-methyl-D-lyxo-hexopyranosly-11α-O- methylbutyryl-12β-O-acetyl-tenacigenin B (63), 3-O-6-deoxy-3-O-methyl-β-D- allopyranosyl-(14)-β-D-oleandropyranosyl-11-O-tigloyl-tenacigenin C (64)和3-O-6-deoxy-3-O-methyl--D-allopyranosyl-(14)--D-oleandropyranosyl-11α-O-2- methylbutyryl-tenacigenin C (65) 第5 This dissertation consists of 5 chapters. The first chapter elaborate the phytochemical investigation of Paeonia lactiflora Pall., and microbial transformation of paeoniforin. The second, third and four chapters elaborate the phytochemical investigation of Saussurea involucrate Kar.et Kir., Zanthoxylum nitidum (Roxb.) DC. and Marsdenia tenacissima (Roxb.) Wight et Arn., respectively. Chapter 5 is a review on chemical constituents and bioactivities of Zanthoxylum species. The part one of chapter 1 focus on the isolation and identification of chemical constituents from P. lactiflora. Fourteen compounds were isolated from the roots of P. lactiflora by repeat column chromatography over normal and reversed phase silica gel. Among them, one is a new compound and the structure was suggested as galloyl-albiflorin by spectral evidence. In addition, two compounds were firstly reported in this plant. The part 2 is about microbial transformation of paeoniforin. Chapters 2, 3 and 4 were isolations and identifications of chemical constituents from S. involucrate, Z. nitidum and M. tenacissima, respectively. From the aerial parts of S. involucrate, 28 compounds including 7 flavonoids and 13 sesquiterpenoids were isolated and identified. Among them, 2 new compounds were characterized as 6-hydroxycostic acid 6--D-glucoside and 11H-11,13-dihydrodehydro- costuslactone 8α-O-(6'-acetyl)-β-D-glucoside, respectively, by means of spectroscopic analysis. Otherwise, 11 ones were firstly reported from this plant. The third chapter is about the phytochemical investigation of Z. nitidum. Sixteen compounds were isolated and identified. Among them, 2 new benzophenanthridine alkaloids were characterized as 8-acetonyldihydrofagaridine and 1,3-bis(8-dihydronitidinyl)-acetone by spectroscopic analysis. The fourth chapter is about the phytochemical investigation of M. tenacissima. Fourteen compounds were isolated and identified. Among them, 4 new compounds, tenacigenosides A~D, were characterized as 3-O-6-deoxy-3-O-methyl-β-D-allopyranosyl-(14)-β-D-oleandropyranosyl-17- tenacigenin B, 3-O-2,6-dideoxy-4-O-methyl-D-lyxo-hexopyranosly-11α-O-methyl butyryl-12-O-acetyl-tenacigenin B, 3-O-6-deoxy-3-O-methyl-β-D-allopyranosyl- (14)--D-oleandropyranosyl-11α-O-tigloyl-tenacigenin C, and 3-O-6-deoxy-3-O- methyl--D-allopyranosyl-(14)--D-oleandropyranosyl-11α-O-2-methylbutyryl- tenacigenin C. Chapter 5 is a review on recent progress in bioactive constituents from plants of Zanthoxylum species.
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多羟基哌啶类化合物通常称为氮杂糖，由于与糖结构的相似性，亚胺基环醇表现出强的糖苷酶和糖基转移酶抑制活性，可调控在生物识别及酶结构控制中起到重要作用的糖蛋白的生物合成与水解。因此这类抑制剂有望成为与糖代谢紊乱有关的疾病的治疗药物，如：抗糖尿病、抗肿瘤、抗溶酶体贮积症及抗病毒感染（包括艾滋病）等药物。正是由于氮杂糖的重要生物活性及诱人的药用开发前景，近年来，有关氮杂糖及其衍生物的合成、生物活性及应用研究备受关注。 本论文探索了一系列的作为潜在的迈克加成中间体1-C-/-5-N-β-1-C--N-1-C-甲氧羰基甲基-N-取代氮杂吡喃糖碳苷衍生物的方法，该转变过程为先通过β-消除得到非环状的α/β5-N-取代氨基与分子内的α/β1,4-亲核加成，其中，2'-酯的环加成立体选择性的得到β1-C-乙酰甲基-N-取代氮杂吡喃糖碳苷衍生物，而2'-酮的环加成得到立体异构体1-C--N-N-取代氮杂吡喃糖碳苷衍生物进一步脱除保护基，得到了一系列新的N- 中间体1-C-(2'-oxoalkyl)-5-N-alkylated glycoribofuranosideC-5C-1C-5(a) 5-5-SN2(b) 5-C-52'-2'-2'- The polyhydroxylated piperidines, commonly be called azasugars. Iminocyclitols and their derivatives have exhibited remarkable biological activity to inhibit glycosidase-processing enzymes, with resulting potential chemotherapeutic applications against diabetes, cancer, lysosomal storage disorders and viral infections including AIDS. Recently, because of the important biological activity and excellent foreground on pharmaceutical application, great attention has been attracted to the synthesis of the new derivatives and analogues. In this dissertation, 1-C-(2'-oxoalkyl)-5-N-substituted-glycoribofuranosides, which used as latent substrates for intramolecular hetero-Michael addition, were converted to 2-ester and 2-ketone aza-C-glycopyranosides by base treatment. The transformation was achieved through β-elimination to an acyclic α/β-conjugated ketone or ester, followed by an intramolecular hetero-Michael addition by the 5-N-alkylated amino group. The 2-ester cycloaddition was highly stereoselective in favor of an equatorial 1-C-substitution while the 2-ketone cycloaddition was produced a pair of stereoisomers of 2′-ketonyl aza-C-glycoside. Additionally, the resultant different N-alkylated aza-C-glycopyranosides could be further prepared for various azasugar library constructions by removal of protecting groups. Synthesis of the key intermediate 1-C-(2'-oxoalkyl)-5-N-alkylated glycoribo- furanoside involved the introduction of 5-substituted amino and 1-C-2-oxoalkyl groups from D-ribose. The 5-alkylated amino was introduced through two methods: (a) the 5-aliphatic series amino synthesized by the nucleophilic substitution of 5-mesylate using neat ethylamine, propylamine, butylamine, and hexylamine, (b) the 5-aromatic series amino synthesized by various aromatic aldehydes with C-5 amino under NaBH4 reduction. The 1-C-2-oxoalkyl groups were introduced through oxidation of the ally group: the 1-C-allyl group was oxidized with Hg(OAc)2 and Jones reagent to the 2-ketonyl C-glycoside; the 1-C-allyl group was oxidized with KMnO4 and CH3I/NaHCO3 to 1-C-methyl acetate glycoside.
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近十年，植物群体遗传学的研究飞速发展，然而与海拔相关的植物群体遗传结构和遗传变异研究却相对较少。到目前为止，还不清楚遗传变异与海拔之间是否有一个通用的格局。在山区，各种生态因子，如温度、降水、降雪、紫外线辐射强度以及土壤成分都随海拔梯度急剧变化，造成了即使在一个小的空间区域，植被类型变化显著，这种高山环境的异质性和复杂性为我们研究植物群体遗传结构和分化提供了方便。沙棘(Hippophea)(Elaeagnaceae)(H. rhamnoides subsp. sinensis)1,800 m 到3,400 m 5 RAPD 和cpSSR 分子标记研究了卧龙自然保护区中国沙棘天然群体的遗传结构和遗传变异。5 A、B、CD 和E1,800，2,2002,6003,000 3,400 m 的5 RAPD实验用11 条寡核苷酸引物，扩增得到151 143 94.7%5 个沙棘群体中，总遗传多样性值(HT)0.289，B群体内的遗传多样性值为0.3155 2,200 mB群体遗传多样性达最大值0.3153,400 m海拔处的E0.098。5 GST0.40640.6%的遗传变异存在于群体间，1,800 mAUPGMAPCoA5 Mantel(r = 0.646, P = 0.011)cpSSR 24 cpSSR 11 2 (ccmp2 ARCP4)4 4 种单倍型，单倍型Ⅰ出现在A B 8 个个体中，CDE CD、E B 18 A 群体不含有。另外两种单倍型Ⅲ和Ⅳ为稀有类型，仅B 4 个个体拥有。这种单倍型分布模式和TFPGA 群体聚类图揭示了，CDE A 群体却是由另一祖先种发展起来的，B B 群体处某个或者某些个体发生了基因突变，具备了适应高海拔环境的能力，产生了高海拔沙棘群体的祖先种。 In recent ten years, studies about population genetics of plants developed rapidly,whereas their genetic structure and genetic variation along altitudinal gradients have beenstudied relatively little. So far, it is uncleared whether there is a common pattern betweengenetic variation and altitudinal gradients. In the mountain environments, importantecological factors, e.g., temperature, rainfall, snowfall, ultraviolet radiation and soil substratesetc., change rapidly with altitudes, which cause the vegetation distribution varying typically,even on a small spatial scale. The mountain environments, which are heterogeneous andcomplex, facilitate and offer a good opportunity to characterize population genetic structureand population differentiation.The species of the genus Hippophae L. (Elaeagnaceae) are perennial deciduous shrubs ortrees, which are dioecious, wind-pollinated pioneer plants. The natural genus has a widedistribution extending from Northern Europe through Central Europe and Central Asia toChina. According to the latest taxonomy, the genus Hippophae is divided into six species and12 subspecies. The subspecies H. rhamnoides ssp. sinensis shows significant morphologicalvariations, large geographic range and dominantly outcrossing mating system. Thesecharacteristics of the subspecies are favourable to elucidate genetic variation and systemevolution. To estimate genetic variation and genetic structure of H. rhamnoides ssp. sinensisat different altitudes, we surveyed five natural populations in the Wolong Natural Reserve at altitudes ranging from 1,800 to 3,400 m above sea level (a.s.l.) using random amplifiedpolymorphic DNA markers (RAPDs) and cpSSR molecular methods. The five populations A,B, C, D, and E correspond to the altitudes 1,800, 2,200, 2,600, 3,000 and 3,400 m,respectively.Based on 11 decamer primers, a total of 151 reproducible DNA loci were yielded, ofwhich 143 were polymorphic and the percentage of polymorphic loci equaled 94.7%. Amongthe five populations investigated, the total gene diversity (HT) and gene diversity within population B equaled 0.289 and 0.315, respectively, which are modest for a subspecies of H.rhamnoides, which is an outcrossing, long-lived, woody plant. The amount of geneticvariation within populations varied from 0.098 within population E (3,400 m a.s.l.) to 0.315within population B (2,200 m a.s.l.). The coefficient of gene differentiation (GST) amongpopulations equaled 0.406 and revealed that 40.6% of the genetic variance existed amongpopulations and 59.4% within populations. The population A (1,800 m a.s.l.) differed greatlyfrom the other four populations, which contributes to high genetic differentiation. A UPGMAcluster analysis and principal coordinate analyses based on Nei's genetic distances furthercorroborated the relationships among the five populations and all the sampling individuals,respectively. Mantel tests detected a significant correlation between genetic distances andaltitudinal gradients (r = 0.646, P = 0.011).Eleven of the original 24 cpSSR primer pairs tested produced good PCR products, onlytwo (ccmp2 and ARCP4) of which were polymorphic. Four total length variants (alleles) werecombined resulting in 4 haplotypes. The haplotype was present in all individuals of population A and 8 individuals of populations B, the other three populations (C, D and Epopulations) did not share. The haplotype was present in all individuals of populations C, D and E and 18 individuals of populations B, population A did not share. The other twohaplotypes and were rare haplotypes, which were only shared in 4 individuals of Ⅲ population B. The distribution of haplotypes and TFPGA population clustering map showedthat the populations C, D and E might be origined from one ancestor seed and population Amight be from another, whereas population B owned information of the two ancestor seeds. Itwas because that gene mutation within some individual or seed in the location of population Bwas likely to happen in the history of H. rhamnoides, which was the original ancestor of thehigh-altitude populations.
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角蟾科（Megophryidae）是以角蟾属（Megophrys Kuhl and Van Hasselt, 1822）为模式属而建立的，隶于无尾目（AnuraAnomocoela）。角蟾科包括2 11 142 种，分布于东洋界，从巴基斯坦、中国西部向东直到菲律宾和苏达群岛；中国有9 75 1）角蟾科蝌蚪的形态多样性分析；（239 30 12s rRNA cytochrome b 14 2 种新的角蟾科蝌蚪类型。A B C 型：新类型，短腿蟾型蝌蚪，一种特化类型，该型蝌蚪在本文中仅包括短腿蟾属的物种；D 2）对角蟾科的分类进行了修订：（123）拟髭蟾亚科分为2 A 4 个属：拟髭蟾属、髭蟾属、齿蟾属、齿突蟾属；掌突蟾族，该族物种具有类型B 2 个属：掌突蟾属和小臂蟾属。34 种蝌蚪类型的演化。（123）短腿蟾型蝌蚪是角蟾型蝌蚪的一种特化类型；（454）分析了角蟾科四种蝌蚪类型与栖息环境的适应演化。（12A D3）蝌蚪口器内部结构的分化揭示了蝌蚪和食性的适应关系，蝌蚪以口部的唇齿与角质颌刮取或吞吸水中的物质，然后，通过口乳突有选择地过滤进入口腔中食物。拟髭蟾亚科蝌蚪的唇齿多而窄，唇齿间距宽，颌鞘粗而稀，反映了其植食性为主的特点；它们的舌前乳突一般为指状，在口腔入口处所占面积小，其机械过滤的作用很多被唇齿和角质颌分担了；而角蟾亚科的蝌蚪，其角质颌弱，其舌前乳突一般为匙状，几乎填满了口腔入口处，因此舌前乳突起了主要的机械过滤作用。The family Megophryidae is the largest and most diverse families inArchaeobatrachia, and most of its species occur in India, Pakistan, and eastward intoChina, Southeast Asia, Borneo and the Philippines to the Sunda Islands. Currently thefamily includes 142 species have been grouped into two subfamilies, Megophryinaeand Leptobrachiinae. The mountains of central and southern China are rich in speciesof Megophryidae, 75 species belong to 9 genera and two subfamilies.The family was supposed to be ideal materials of studies in many fields of biology,such as taxonomy, evolution, systematics, ecology, and biogeography. Recently, therehave a great development in taxonomy and systematics of megophryids throughstudied by morphology, paleontology, cytology, ecology, and cladistics. However,larvae of megophryids were generally unknown, although the tadpoles might be veryimportant for above studies.In this paper, we examined the evolutionary scenario of the tadpoles morphologyin the context of a phylogenetic framework. Our objectives are (1) to evaluate thedivergence of larval body shape and oral discs in the family Megophryidae, (2) toexplore the evolutionary trends of the larvae in megophryidae, and test if thefunnel-shaped oral disc is apomorphic, and (3) to explore the relationship of the larvalstructure, diet and microhabitat.We examined larval morphology of 30 megophryid species, the larval body shape,oral discs, the buccopharyngeal cavity, and jaw sheaths and denticles of the Chinesemegophryid frogs were re-examined. We constructed a phylogeny of the species on thebasis of published mitochondrial cytochrome b and 16S rRNA gene segments usingpartitioned Bayesian analyses. Furthermore, hypothetical changes of larval morphologywere inferred using parsimony principle on the phylogeny. The results showed that:1) Four tadpole types in Megophryidae. The larval morphological charactersseries in Chinese megophryids fall into four general categories according to the bodyshape and oral discs: (A) Leptobrachiini type, species from genera Leptobrachium,Oreolalax, Scutiger and, Vibrissaphora share this type of tadpoles. (B) Leptolalax type,species of genus Leptolalax have this type of tadpoles. (C) Brachytarsophrys type,species of the genus Brachytarsophrys have this type of tadpoles. (D) Megophryinitype, species of the genera Atympanophrys, Ophryophryne, and Xenophrys share this type of tadpoles. Of which B and C are two novel types.2Taxonomic implications. The present study leads us to reconsider the generalclassification of tribes attributed to members of Megophryidae. More specifically,concerning the phylogenetic relationships and the two novel tadpole types describedherein, we propose a provisional taxonomy for the family but suggest that further taxasampling of other megophryids be performed to confirm this taxonomic change. TheMegophryidae is composed of two subfamilies (Leptobrachiinae and Megophryinae).The Leptobrachiinae was recogonized the two tribes: (1) tribe Leptobrachiini sensuDubois, corresponding to the tadpole of type A, including four genera, i.e.,Leptobrachium, Oreolalax, Scutiger and, Vibrissaphora; (2) tribe Leptolalaxini,corresponding to the tadpole of novel type B, including two genera, i.e., Leptolalaxand Leptobrachella. However, the relationships among the genera of Megophryinaewere largely unresolved, they recognized no monophyletic groups above the generalevel. A more thorough sampling will likely foster a better taxonomic solution.3) The larval evolutionary scenario in Megophryidae.Type A is characteristicof normal-mouthed with multiple tooth rows, representing the tadpole type of theMRCA of Chinese megophryids. Type B is characteristic of normal-mouthed withreduced tooth rows, prolonging labium, and integumetary glands. Type C ischaracteristic of no labial teeth and smaller umbeliform oral disc. Type D ischaracteristic of no labial teeth, enlarged umbeliform oral disc, representing the tadpoleof the MRCA of subfamily Megophryinae. A previous hypothesis, referring tofunnel-shaped oral discs as an apomorphy, is supported.4) The larval adaptation to habitats in Megophryidae. Tadpoles generallyadhere to substrates using their mouths, and the microhabitat that the tadpoles occupyreflects the degree of adhesion and oral complexity. The morphological changes inmegophryid tadpoles virtually allow a progressive adaptation to a changing habitatfrom faster water to slower water. Within the tadpoles of Type A to type D, the TOTbecomes smaller and smaller, and the oral disc orientates from anteroventral toumbelliform upturned, and eye position orientates from dorsal to lateral, and the trunkis more and more depressed and tail becomes relatively longer and slender. Within therunning water, the normal-mouthed with multiple tooth rows of Leptobrachiini tadpoles are correlated with lotic-suctorial, benthic feeders with anteroventral oraldisc and the largest body. With the waters velocity decreasing, the lotic-adherentfeeders of Leptolalax tadpoles have tube-shaped labium with reduced tooth rows andintegumetary glands. And then, the smaller umbeliform in Brachytarsophrys tadpolesand the enlarged umbeliform oral disc in the Megophryini tadpoles are inhabitmicrohabitats of non-flowing backwaters of rivers, indicative of adaptive traits oflotic-neustonic surface feeders. The scheme of megophryid tadpoles andmicrohabitats provided the first clear evidence which congruent with the hypothesis ofAltig and Johnston (1989). The ecological divergence plays a general role in thedivergence and evolution of megophrid larvae. There is a definite correlation amongthe buccopharyngeal cavity, diet and feeding mechanisms, the tadpole graze orswallow the food particles, then through papillae which like a sieve and sort out foodparticles to the oesophagus. The tadpole of Leptobrachiinae possess multiple toothrows, wide intertooth distance as well as thick and sparse jaw sheath, these tadpolesinhabit bottom of the streams and graze on epiphyton or major detritus of organicmatter on the substrates, their prelingual papillae like single finger, the mechanicalpurpose of papillae served share in by tooth and jaw. The tadpoles of Megophryinaeoccur near the water surface of small streams and are the filter feeder, their dietincludes plankton and organic debris floating on the water surface, those tadpolepossess weak jaw, their prelingual papillae like spoon, the mechanical purpose ofpapillae served mostly for sieve.
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依据线粒体上ND2和CO1两个变异较大的基因序列分析了香港地区香港湍蛙717种群，戴云湍蛙11 1 香港湍蛙核苷酸传多样性较低，从其遗传多样性信息、单倍型网络分析、中性检验值以及岐点分布结果一致显示香港湍蛙很可能经历了瓶颈后的扩张，种群正在由一个较小的有效种群大小迅速增长, , , 时间尚短（Nei M et al1975，Avise J C，20002003 分子变异分析结果显示香港湍蛙种群间存在较多的基因交流，且系统发育树上各种群间交叉在一起，没有形成与地理单元相关的分支，而从其单倍型网络看，他们源于共同的祖先，是一个单系群，与地理单元间没有形成显著的遗传分化。因此应作为一个进化显著单元（ESU）。结合其与其他湍蛙发育关系及遗传距离以及野外采集信息认为香港湍蛙只在香港地区有分布，属于香港特有种。该物种内遗传多样性较低，又属于世界自然保护联盟红皮书中的近危种，同时也是《野生动物保护条例》中的受保护野生动物，且由于香港城市建设等使得其栖息环境受到威胁，因此在香港特别行政区应该受到重点保护。 从单倍型分布和核苷酸多样性可以看出大榄涌种群和城门种群具有较高的单倍型多样性和核苷酸多样性，应该作为保护的重点区域。 2. 华南湍蛙东、南沿海种群间系统关系 华南湍蛙分布广，各种群存在着丰富的遗传多样性信息且中部种群广西龙胜和湖南张家界种群核苷酸多样性明显高于其他边缘种群华南湍蛙。种群间几乎没有基因交流，且各种群间无共享单倍型，可见已形成了显著的遗传分化。各种群间遗传距离都较远，其中广东南昆山种群以及福建三港种群与其他种群距离最远，因此可以推测其他种群（广东深圳、香港大屿山、广西龙胜和防城以及湖南张家界种群）可能为独立进化的种群。但是否是一新种或一隐存种，还需要结合形态学进行更深入的研究。 本研究中无论从系统关系看还是从遗传距离看，大屿山种群与深圳种群最近，支持陈坚峰等将其定为华南湍蛙，即华南湍蛙新增一个分布点：香港大屿山。 系统树上广西防城种群（支B）与龙胜和湖南种群（支ACD）形成姐妹群，可能粤北和粤中的环境及气候较复杂因此与粤南其他种群形成了明显的隔离。同时可以看出华南湍蛙种群遗传分化与地理距离没有显著的相关性。 3. 四种湍蛙间的系统关系 根据线粒体CO1基因建立四种湍蛙间的系统关系及其遗传距离，很清楚地看到，香港湍蛙与戴云湍蛙关系很近，而华南湍蛙则与武夷湍蛙较近。然而，戴云湍蛙同一个种群内部共有两个单倍型DY1和DY2，且两个单倍型间遗传距离大于DY1与香港湍蛙间遗传距离，更远远大于香港湍蛙种群内部的距离，即戴云湍蛙内部两个单倍型间遗传距离达到了种级水平，同样在系统发育树上这两个单倍型与香港湍蛙形成并系。但是，戴云湍蛙种内在形态上差异不显著。因此，其是否属于萌芽物种分化形成（budding speciation 与戴云湍蛙香港湍蛙关系类似，从系统树上看华南湍蛙不形成单系，而是分成两个大支，与武夷湍蛙形成并系，且福建和南昆山的华南湍蛙与武夷湍蛙遗传距离远大于武夷湍蛙种内福建种群与浙江种群的遗传距离，达到了种级分化水平。由此，可以推断武夷湍蛙是有效种。系统树上广东深圳、香港大屿山、广西防城和龙胜以及湖南张家界种群与华南湍蛙福建及南昆山各种群间遗传距离已超出了种内各种群间的遗传距离，但是至于这一支是否应为另外一个种，有必要扩大采样，并结合核基因及形态信息进行进一步研究。 MtDNA of ND2 and CO1 gene were used to investigate genetic diversity of Amolops in Hongkong .We collected seven populations of A. hongkongensis,，one population of A.ricketti from Hong Kong and other seven populations of A.ricketti from East and South of Chinese mainland. As well as one population of A. daiyunensis and one population of A.wuyiensis Phylogenetic relationship were analyzed of four species. Discussed whether A.hongkongensis is an endemic species and how can we make the conservation and management decisions. 1. Conservation Genetics of A. hongkongensis A. hongkongensis has a low nucleotide diversity, the results of genetic diversity, haplotype network, neutrality test and the mismatch distributions indicate that A. hongkongensis experienced a recent expansion after a bottle neck. They had enough time to accumulated haplotype diversity, but its too short to have a high nucleotide diversityNei M et al，1975Avise J C2000Li et al2003. The result of AMOVA reveals that it has much gene exchange among the populations of A. hongkongensis. The clades of the phylogenetic tree were mixed together, no significant genetic differentiation among 8 populations and they share the same ancestor from the network analysis, these indicate that they are monophyly and should be protected as one ESU. Combined with the information of relationships of interspecies, genetic distance and distribution investigate, We conclude that A. hongkongensis is an endemic species of Hong Kong. Considering on the status of low genetic diversity in A.hongkongensis, and this species was listed in the IUCN red list as near threatened, as well as listed in the <protected wild animal>. Furthermore, it’s habitat loss and degradation more rapidly as the human activity got higher and higher. So its urgent to protect them in Hong Kong. Our results suggest that Tai Lam Wu and TAI MO Shan -Shing Mun populations have the higher priority to be protected because their higher genetic diversity. 2Phylogenetic relationships among populations of Amolops ricketti from the Southern and eastern China A. ricketti has the considerable genetic diversity of mitochondrial haplotypes within and among populations, and Mitochondrial DNA diversity was higher in populations at the central area of the present distribution range of the frogi. e. the Longsheng population and Zhangjiajie population, than at the edges of their distribution range. They have no share haplotype among populations, and have a significant genetic differentiation. Genetic distance is high among the populations, especially the distance of Nankun and Sangang group with others, which suggested that they evolved independently. May be there is a cryptic species or a new species, a further study is needed. The results of gene tree and the genetic distance clearly demonstrate that the population from LanTau island is A. ricketti, so we agree with Chen et al(2005) . That means A.ricketti have a new distribution site: LanTau island, HongKong. Phylogenetic relationships were analyzed through NJ and Mrbayes methods and got a consistent topological structure, the structure indicated that the ingroup were comprised four groups. Populations Longsheng and Zhangjiajie were first clustered as clade A; Populations Fangcheng was clustered together (clade B) as a sister group to clade A；Populations Shenzhen and Lantau island were sister groups and clustered as clade CThen the clade D included populations Nankunshan and Nanling in Guangdong province and Sangang in Fujian province. 3. Phylogenetic Relationships among these four specises Phylogenetic relationships based on 1503bp CO1 gene and the genetic distance show that A. hongkongensis close to A. daiyunensis whereas A.ricketti near to A.wuyiensis. Nevertheless, there are two haplotypes in A.daiyunensis and the genetic distance between them higher than the distance between DY1 with A. hongkongensis. A. hongkongensis is nested in the paraphyletic ancestral species A. daiyunensis. Without significant difference in the morphological characters, So, we considered both A.daiyunensis and A.hongkongensis are valid species, may be this represents a case of ‘budding speciation like Batrachuperus pinchonii(Fu and Zeng,2008) in the population of A. daiyunensis. Just like two species above A. wuyiensis and A. ricketti are not monophyly, instead, A.wuyiensis is nested in the paraphyletic ancestral species A.ricketti. We need do more research to make sure whether they are new species.
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本文叙述了影响甲烷氧化细菌沼气甲基产孢弧菌81Z菌株生长和甲烷单加氧酶(MMO)81ZPO43-(>8mM),NH4+([NH4cl]>500mg/l)[CuSO45H2O]在04mg/l范围内。生长随[Cu2+]升高而加强，低[Cu2+](0.1mg/l CuSO45H2O)培养基中，添加Cocl26H2O(0.238mg/l)81ZMMO81ZMMOMMO,MMOL最适PH6.26.44℃相对稳定，其产生不受培养基中[Cu2+]调控能与甲醇-400μM[Cu2+][Cu2+]81ZMMCPH7.0，4DE-52分离为三组分：ABC。为了获得沼气甲基产孢弧菌81Z细胞MMO的最佳催化活性，①采用高[Cu2+]培养基进行发酵罐培养，收集对数生长中期的细胞；②选择反应缓冲液PH6.35mMMMO15.9nmol/minmg干细胞，是以前报道的该菌株活性0.97nmol/min·mgSome factors which influence growth and MMO activity of Methylosporovibrio methanica 81Z were described. The growth of Methylosporovibrio methanica 81Z is inhibited by high concentration of PO43-(8mM)or NH4+(500mg/lNH4cl). The growth of Methylosporovibrio methanica 81Z increased with rising of copper concentration up to 4mg/l CuSO4·5H2O. At low copper concentration(0.1mg/lCuSO4·5H2O),adding Cocl26H2O(0.238mg/l)could enhance the growth of Methylosporovibrio methanica 81Z.With batch culture of Methylosporovibrio methanica 81Z in a fermentor, after lag phase, the activity of MMO reached the highest level rapidly and steady until later log phase, then falled to initial level.MMOL activity differenct from that of two types of MMO reported before was found from Methylosporovibrio methanica 81Z with optimum PH value from 6.2 to 6.4 and relative stabilty at 4℃. Synthsis of the MMOL was not regulated by copper concentaration in medium. Its activity could couple with methane-l-methanoldehydrogenase system, and in cell-free extract, were inhibited by 400m copper ion. At low copper concentration(0.1mg/lCuSO4·5H2O) and in a fermentor, Methylosporovibrio methanica 81Z could syntheis soluble MMO similar to solble MMO reported before by Palton and Patel. Its optimum PH value was 7.0. It was unstable at 4. It could be resoluted into three components: A, B, and C. It was effentive for obtaining the maxtmum MMO with Methylosporovibrio methanica 81Z that (1) to keep high copper concentration(4mg/lCuSO45H2O) in a fermentor and harvest cell at middlel lag phase;(2) to choose 6.3 as the PH value of reaction buffer;(3)and to add 5mM methanol or formate into reaction system. In this dy, the MMO activity of cells of Methylosporovibrio methanica 81Z was reached 15.9 nmol/min.mg, dry weight, sixteen times as high as the value(0.97nmol/min.mg, dry weight) reported with the same strain.
