苏铁与蓝细菌的共生

蓝细菌能与不同进化阶段的植物代表种共生，苏铁是能与蓝细菌共生的唯一的裸子植物。本文从蓝细菌与苏铁超显微结构、共生蓝细菌的多态性、蓝细菌对苏铁珊瑚状根的侵染和研究展望等几个方面阐述了苏铁与蓝细菌的共生关系，认为从分子水平上揭示蓝细菌与苏铁形成共生固氮体系的系统性和共生双方的遗传多样性，不仅具有重要的意义，而且也具有广阔的应用前景。     

高温高压下氧逸度的就位控制

建立了一种高温高压下氧逸度就位控制的新方法，该方法中，使用了由参考缓冲剂，上部氧离子导体（ＹＳＺ）圆片，样品，下部ＹＳＺ圆片及氧库按序叠合成的圆柱状样品组合。通过在样品与氧库间施加一驱动电压，氧库中氧可被抽出注入样品或样品中氧可被抽出注入氧库，从而样品中氧逸度可独立于温度，压力得到任意甚至连续（若样品本身属性允许）的就位控制，通过测量样品与参考缓冲剂间电压，可对控制过程中样品中氧兔度及其变化实行就     

中国色球藻科一个新纪录属

为了解贵州省树皮藻类物种多样性，在贵州省遵义市采集的样品分析中发现了色球藻科蓝叠球藻属（Cyanokybus）的分布，该属为单种属，仅委内瑞拉蓝叠球藻（Cyanoky busvenezuela）1个种．依据采集的标本对该属种形态特征进行了补充描述；对该属种的生境特征、地理分布进行了初步的讨论．研究结果对蓝叠球藻属（Cyanokybus）区系分布、起源演化、生态特征等后续研究具有较大的参考价值．     

VSK分选在两种低品位铁矿粉分级中的应用评估

低品位铁矿粉曾经主要被认为是废弃物。然而，随着对高级铁矿石需求的不断增加和铁品位的逐渐降低，目前铁矿石行业正把重点放在低品位铁矿粉的选矿上。此外，由于许多矿点缺水和各国政府新的节水政策，必须研究适当的干式选矿路线。本文评估了干式分级装置（VSK分离机）在提高两种低品位印度铁矿粉（样品1和样品2）铁含量方面的效果。矿物学研究（包括扫描电子显微镜和X射线衍射）表明，样品1是一个低品位的蓝色粉尘样品（51.2wt% Fe），样品2（53.3wt% Fe）中除赤铁矿和石英外，还含有针铁矿。采用Box–Benkhen统计设计进行了试验，结果表明，风机转速是VSK分离器中对产品质量影响最大的运行参数，其次是进料速率。在最佳操作因子水平下，样品1可得到含~55wt%铁的细粒产品，产率为~40%，而样品2可在产率为~85%的情况下升级为~56wt%铁。结果表明，VSK分选机可作为选矿回路中一种有效的中间单元操作，提高铁矿粉的含铁量。     

中国木犀科代茶植物的多样性与开发状况

文献研究、市场调查和实地考察的结果表明，我国民间使用的木犀科植物代茶植物至少有17种，其中以妇女贞属中代茶植物种类最多(10种)，其余的代茶植物分布于流苏树属(1种)，雪柳属（1种），素馨属（1种），木犀属（2种）以及丁香属(2种)。有9种木犀科代茶植物在我国不同文献、不同地域或不同民族中被称之为“苦丁茶”。在我国所有的木犀科代茶植物中，以粗壮女贞和茉莉花最具影响，已在西南地区大面积人工栽培和产业开发。     

长庆油田金属管材的腐蚀性细菌类群研究

对长庆油田101站和马岭42＃井注入水，原油及油水混合样品中可引起金属管材腐蚀的细菌进行分离，鉴定。结果：表明，这些样品中都含有硫酸盐还原菌（Sulfate-reducing Bacteria,SRB)，铁细菌（Iron Bacteria,IB)及少量硫杆菌，其中硫酸盐还原菌种类较多，主要为脱硫弧菌属和脱硫肠状菌属，铁细菌主要为纤发菌属（Leptothrix)，赭色菌属（Ochrobium)及鞘铁菌属（Siderocapsa)，各样品中的硫杆菌主要是脱氮硫杆菌，硫酸盐还原菌与铁细菌的存在对采油管线造成了腐蚀危害，讨论了这类细菌在油田的分布，以便更有效地防止油田环境中微生物对金属管材的腐蚀。     

永定河山峡与城市段微生物群落结构季节变化

微生物是河流生态系统的重要组成部分，其群落结构会随着时空差异发生改变. 本研究于8月和11月分别采集永定河山峡段和城市段12个点位的样品，采用高通量测序技术研究其群落结构组成及季节演替情况，共检出微生物38门864属，其中蓝细菌门（Cyanobacteria）、放线菌门（Actinobacteria）、变形菌门（Proteobacteria）和拟杆菌门（Bacteroidetes）在群落结构组成中占主要优势. 在时间与空间变化中，8月与11月，山峡段与城市段的永定河微生物群落结构都表现出明显差异，总体来看，8月水体的微生物多样性高于11月份，季节变化使得山峡段微生物群落结构发生了较大变化，而对城市河段的影响不大. 此外，人类活动没有对城市河流的群落多样性造成显著影响，但会使得群落的丰富度显著降低.      

青城山藻类植物初步研究

对青城山部分水体及潮湿环境中的藻类植物的种类及生态分布情况进行了调查研究，该地区的藻类植物共有21科26属45种．绿藻门植物种类最多，共18种（46．67％），分别属于12科，10属；硅藻门12种（31．11％），分别属于6科6属；蓝藻门14种（24．44％），分别属于4科7属；金藻门1种（2．22％）．     

16S rRNA基因的PCR-DGGE技术分析茶尺蠖幼虫肠道细菌种群结构及多样性

利用16S rRNA的PCR-DGGE（变性梯度凝胶电泳）技术分析研究了茶尺蠖肠道内细菌的种类与多样性.通过对16S rRNA序列分析,从茶尺蠖野外种群肠适中鉴定了11种细菌,这些细菌分属于沃尔巴克氏菌（Wolbachia）、肠杆菌属（Enterobacter）、沙雷氏菌属（Serratia）、梭菌属（Clostridium）、肠球菌属（Enterococcus）、暂定类群EO1;其中以肠杆菌、沃尔巴克氏菌、沙雷氏菌属最为常见.另外,也鉴定了一种茶树叶绿体上的16SrRNA基因.茶尺蠖幼虫体内的共生菌多样性分析结果,将会为害虫综合治理提供一条全新的探索途径.     

植食性昆虫、植物和共生微生物的功能关联

植食性昆虫和植物均能与微生物形成密切关系，它们各自的生态功能及相互关系也常被共生微生物所影响。近年来，随着分子水平研究方法的进展，植食性昆虫和植物中很多可遗传共生微生物（细菌、真菌等）被发现。共生微生物能够在营养、生殖、防御和解毒等方面给宿主带来显著影响，并与宿主形成竞争、互利或寄生等关系。植食性昆虫体内的含菌胞、肠道、血淋巴、唾液腺等常含有重要功能的共生微生物。新的分子生物学手段和高通量测序技术的应用使得我们能够增加对宿主和共生微生物（即使处于低丰度）之间关系的了解。本文尝试总结了植食性昆虫和植物共生微生物的多样性及其关系、昆虫和植物互作机制、昆虫共生菌解毒植物毒素等方面的近期证据，突出强调了应以系统观思维来理解共生微生物、植食性昆虫和植物间的功能关联，并就将来值得研究的问题提出了建议。     

RAPD analysis of genetic variability among Stylosanthes guianenesis accessions of resistant and susceptible to the stylo anthracnose

Stylosanthes guianenesis Sw. is an important tropical forage legume grown and utilized in the tropics and the subtropics of South China. Anthracnose, caused by Colletotrichum gloeosporioides (Penz.) Sacc., is a major constraint to the extensive use of Stylosanthes. Forty-five accessions of S. guianensis were assessed with RAPD for genetic diversity and for resistance to anthracnose. RAPD analysis was performed using twenty primers screened from 200 arbitrary oligonucleotides, and a 71.5% level of polymorphism was found. The dendrogram obtained with unweighted pair group method of averages (UPGMA) based on the RAPD data showed genetic similarity from 50% to 94% among all stylo accessions, and fourteen clusters were defined at 66.5% genetic similarity. Two strains of C. gloeosporioides from stylo in China were used for anthracnose resistance screening. All plant accessions showed variation in the reaction to two strains and the correlation of resistance had a value of 0.904. Multiple correspondence analysis displayed a random distribution of the resistance or susceptibility response with respect to the genetic diversity measured by RAPD analysis except one group. Mean distance was also calculated to determine the diversity within clusters. From our results, the RAPD analysis is an effective and efficient technique of providing quantitative estimates of genetic similarity among stylo accessions.     

西藏石榴野生群体的SSR遗传多样性分析

【目的】调查西藏地区野生石榴种质资源,分析西藏野生石榴群体的遗传多样性和遗传结构,为野生石榴资源的保护和利用提供理论依据。【方法】使用13对SSR引物对3个自然群体共42份西藏地区野生石榴种质资源材料DNA进行PCR扩增,毛细管电泳检测扩增片段长度,使用GenAlEx和Arlequin等软件对SSR数据进行分析。【结果】13对引物共检测到44个等位基因,平均3.385个,引物的平均有效等位基因数(N_e)、香农信息指数(I)、期望杂合度(H_e)和多态信息量(PIC)分别为1.971、0.771、0.481和0.393。3个野生群体的平均有效等位基因数(N_e)、平均香农信息指数(I)和平均期望杂合度(H_e)分别为1.867、0.646和0.421,林芝b(LZb)群体的遗传多样性水平高于其他2个群体。AMOVA分析表明,群体内遗传变异高达88.43%,3个群体间的遗传分化系数(F_st)为0.116。种质聚类分析将供试种质划分为3个亚群,结果与种质地理来源具有一定关联性。遗传结构分析显示西藏野生石榴有4个可能的基因库来源。【结论】13对SSR引物可用于西藏野生石榴种质的遗传多样性等研究。西藏野生石榴种质的遗传变异主要存在于群体内;林芝b(LZb)群体遗传多样性最高,遗传结构复杂,且含有最多的野生种质采样点,可予以优先保护。     

Genetic variations of glycinin subunit genes among cultivated and wild type soybean species

Glycinin is a predominant storage protein in most soybean accessions. It is a hexamer constituted by five major subunits, which can be classified into two groups. Group I contains G1, G2 and G3, and Group II contains G4 and GS. The genes encoding these subunits have been designated from Gyl to Gy5, respectively. In the present study, Gyl genomic fragments were cloned from wild accessions of subgenera Glycine glycine, Glycine soja and a cultivar of Glycine max. Their sequences and the deduced amino acid sequences were compared. The residues critical for assembling of G1 subunits from the wild perennial accession were conservative. The Gy4 fragments were cloned from two wild perennial accessions and compared with that from subgenus Soja. The intron 3 of Gy4 had abundant variations between the subgenera G. soja and G. glycine as well as within the subgenus G. glycine. Abundant variations existed in the disordered regions 3 and 4 of G4 subunits from two wild perennial accessions. The genomic organization of glycinin genes was analyzed in 19 accessions from subgenera Soja and Glycine. The hybridization patterns were identical among the accessions of subgenus Soja. On the contrary, abundant polymorphisms existed between the accessions from subgenus Glycine. These results indicated that glycinin genes have high degree of conservation within subgenus Soja but more variations within subgenus Glycine.     

Genetic variations of glycinin subunit genes among cultivated and wild type soybean species

Glycinin is a predominant storage protein in most soybean accessions. It is a hexamer constituted by five major subunits, which can be classified into two groups. Group I contains G1, G2 and G3, and Group II contains G4 and G5. The genes encoding these subunits have been designated from Gy1 to Gy5 , respectively. In the present study, Gy1 genomic fragments were cloned from wild accessions of subgenera Glycine glycine, Glycine soja and a cultivar of Glycine max . Their sequences and the deduced amino acid sequences were compared. The residues critical for assembling of G1 subunits from the wild perennial accession were conservative. The Gy4 fragments were cloned from two wild perennial accessions and compared with that from subgenus Soja . The intron 3 of Gy4 had abundant variations between the subgenera G. soja and G. glycine as well as within the subgenus G. glycine. Abundant variations existed in the disordered regions 3 and 4 of G4 subunits from two wild perennial accessions. The genomic organization of glycinin genes was analyzed in 19 accessions from subgenera Soja and Glycine . The hybridization patterns were identical among the accessions of subgenus Soja. On the contrary, abundant polymorphisms existed between the accessions from subgenus Glycine . These results indicated that glycinin genes have high degree of conservation within subgenus Soja but more variations within subgenus Glycine .     

Cupriavidus metallidurans CH34中2个苯酚降解基因簇的筛选与功能鉴定

Cupriavidus metallidurans(C.metallidurans)CH34是一种重金属耐受性细菌,能在以苯酚、甲苯酚、苯甲酸、苯胺等芳香族化合物为唯一碳源和能源的培养基中生长,其基因组中含有2个苯酚降解基因簇.以载体pIndigo-BAC 5构建C.metallidurans CH34的细菌人工染色体(bacterial artificial chromosome,BAC)文库,获得约3万个克隆,平均插入片段大小为30 kb,插入频率为98%,推测该文库覆盖CH34基因组约1 240倍.用PCR筛选文库中的3 000个单克隆,共获得9个阳性克隆,其中5个克隆含有长基因簇,4个含有短基因簇,并从中得到含有全长苯酚降解基因簇的克隆.利用以苯酚为唯一碳源的无机盐培养基,研究2个基因簇在大肠杆菌中的表达情况.结果显示,两个基因簇均表现出了苯酚降解能力,短簇的降酚能力要优于长簇.     

Primary structure of helix C to helix G of a new retinal protein in H.sp.xz515

The gene fragment encoding the retinal protein from helix C to helix G in a new strain of halobacteria, H.sp.xz515 has been amplified by PCR method. The nucleotide sequence of this fragment has been determined. The deduced amino acid sequence has been compared with halobium br and other two br-like proteins, ar-1 and ar-2. Results show that those amino acid residues in br, essential for proton pumping and binding to retinal, are conserved. The residue M145 in br may be important for isomerization reaction of retinal.     

Sequence analysis of a 7.3 kbBam H I genomic fragment of fowlpox virus strain 282E4

A 7.3 kb BamH I genomic fragment from fowlpox virus (FPV) strain 282E₄ has been sequenced. After comparison with the FPV sequences collected in Genbank, and the entire genomic sequence of vaccinia virus (VV) strain Compenhagen, a ll.2 kb BamH I fragment from FPV strain Munich HP-438 has been found homologous to the fragment. Every predicted open reading frame (ORF) within the fragment has been compared with the ORFs of VV strain Copenhagen at the amino acid level. The signal peptide and transmembrane region of each peptide encoded by each corresponding ORF predicted in the fragment have been studied as well.     

Sequence analysis of a 7.3 kb Bam H Ⅰ genomic fragment of fowlpox virus strain 282E_4

A 7.3 kb BamH I genomic fragment from fowlpox virus (FPV) strain 282E4 has been sequenced. After comparison with the FPV sequences collected in Genbank, and the entire genomic sequence of vaccinia virus (VV) strain Compenhagen, a 11.2 kb BamH I fragment from FPV strain Munich HP-438 has been found homologous to the fragment. Every predicted open reading frame (ORF) within the fragment has been compared with the ORFs of W strain Copenhagen at the amino acid level. The signal peptide and transmembrane region of each peptide encoded by each corresponding ORF predicted in the fragment have been studied as well.     

鸡传染性支气管炎病毒(IBV)H52疫苗株S1基因的克隆与序列测定

根据国外已发表的鸡传染性支气管炎病毒(IBV)S1基因序列。设计了一对引物并以RT-PCR特异性扩增出IBV H52疫苗株的S1基因，基因产物大小为1．62kb，与设计相符，对其进行序列测定后，与其他标准毒株H120，M4l，BEAU株的S1基因进行同源性比较，结果表明，H52株与H120，M41和BEAU株的核苷酸序列的同源性分别为91．1％，96．9％和96．8％，由此可以看出，IBVH52疫苗株与标准毒株在Sl基因上具有高度的同源性。     

一个假单胞菌MY1402基因启动子的分离与鉴定

利用构建的启动子探针载体pUE,以大肠杆菌(Escherichia coli)DH5α作为宿主菌,从耐低温假单胞菌(Pseudomonas sp.)菌株MY1402分离基因启动子片段,获得7个具有不同大小的启动子功能片段的重组子,命名为pUE1～pUE7.将其中具有p1片段的重组子PUE1导入假单胞菌MY1402中进行卡那霉素耐受浓度分析,结果显示阳性转化子MY1402/pUE1的最高耐受浓度为250 mg/L,而且在相同抗生素浓度下培养温度从28℃降到15℃并不影响转化子MY1402/pUE1的生长,表明pUE1中的插入片段p1具有低温启动子的活性.将所预测的p1核心序列p1a通过化学合成并连接到探针载体pUE上,构建出重组质粒pUE1a并转化MY4102中进行功能分析.结果显示,28℃条件下p1a片段仍保持相同强度的启动子活性,但15℃条件下活性下降明显,卡那霉素质量浓度高于100 mg/L基本没活性,表明p1a两端序列可能与p1低温转录启动活性有关.