两种肚倍型蚜虫之两种同功酶及可溶性蛋白的比较

应用电泳分析方法,对青麸杨上幼锤形信子与长枣形倍子内蚜虫进行了酯酶同功酶、过氧化物同功酶及可溶蛋白质的比较研究。结果表明：经形态学鉴定同为肚倍蚜可致瘿形成纺锤形与长枣形倍子。2种倍形内蚜虫在可溶性蛋白及酯酶同功酶上有较大差异。相异系数分别为02571,0067。说明肚倍蚜种内已出现分化,不同变形体倍子内蚜虫在分子水平上已具有向不同生物型分化的趋势。     

植物重要功能基因研究进展及其应用

随着越来越多植物全基因组测序的完成,植物基因研究的重点将逐渐从基因的发现转移到对基因功能的研究上来。近年来,植物基因功能的阐述日益深入,尤其是与作物产量和抗性相关的重要农艺性状调控机理的研究更加引人注目,一些具有应用价值的功能基因相继被鉴定并得到功能注释。该文综述植物功能基因研究领域近年来的主要进展,着重介绍具有应用前景的重要功能基因的研究。同时,对目前利用基因工程、分子标记辅助选择等于段改良作物的现状及其前景进行讨论。     

Tropic1808基因重组蛋白单克隆抗体的制备及鉴定

目的：制备Tropic1808基因重组蛋白的单克隆抗体,并对其生物学特性进行鉴定。方法：用Tropic1808基因重组蛋白作为抗原免疫BALB/C小鼠,取小鼠脾细胞与小鼠骨髓瘤（SP2/0）细胞融合,经ELISA筛选和有限稀释法获得分泌单克隆抗体的细胞株,Western Blot等方法对其生物学特性进行鉴定。结果：获得2株识别Tropic1808基因重组蛋白的单克隆抗体的细胞株Ⅱ4B、Ⅲ4C。WesternBlot法显示该抗体特异性地识别Tropic1808基因重组蛋白;ELISA法测定杂交瘤细胞培养上清及体内成瘤后产生的腹水的抗体效价分别为1：80、1：600;杂交瘤细胞染色体数平均为90-100;亚类鉴定单抗的重链为小鼠IgG1,轻链为κ型。结论：成功地制备了Tropic1808基因重组蛋白的单克隆抗体,为进一步研究Tropic1808基因重组蛋白的功能提供了良好的基础。     

Precise mapping of a quantitative trait locus interval for spike length and grain weight in bread wheat (Triticum aestivum L.)

The spike characteristics length, spikelet density and fertile floret number are related yield components and are important in cereal improvement. QSpl.nau-2D is a major quantitative trait locus controlling spike length (SPL) detected in the recombinant inbred line population developed by crossing wheat (Triticum aestivum) cultivars Nanda2419 with Wangshuibai. In this study, to validate its genetic effect and determine its precise location, QSpl.nau-2D’s near-isogenic line (NIL) was developed using Mianyang99-323 as the recurrent parent through marker-assisted selection. Field trials showed that the NIL not only had significantly longer spikes on average than the recurrent parent but also had significantly higher grain weight, but did not differ in spikelet number and kernel number per spike. In the F2 population derived from a cross of the NIL with Mianyang99-323, QSpl.nau-2D functioned like a single gene and conditioned the SPL in a partially dominant manner, and was thus designated as HL1 (for head length). To precisely map HL1, 89 recombinants, consisting of 11 genotypes, were identified in the NIL-derived F2 population of 674 plants by using markers in the Xwmc25–Xgpw4080 interval. Phenotyping these lines showed that the introduction of a 0.9-cM interval flanked by Xcfd53 and DG371 in Nanda2419 resulted in longer spikes and a higher grain weight in the NIL. The availability of markers closely linked to HL1 could facilitate its use in breeding programs.     

维生素B型氨基酸衍生维生素的生物合成及功能研究

氨基酸衍生维生素是以氨基酸为前体合成的维生素,主要为维生素B和E家族的维生素,其生物合成方式主要为氨基酸整合和转氨作用。氨基酸衍生维生素在大多数真核生物中主要是作为辅被用物和辅因子,缺乏某些维生素会使动植物患病。本文主要对氨基酸衍生维生素中的维生素B家族的生物合成及功能进行综述,概述了氨基酸在B族维生素生物合成中的作用、不同物种中B族维生素的含量水平以及B族维生素的作用。     

胡杨甜菜碱醛脱氢酶基因的功能分化

甜菜碱醛脱氢酶(BADH)在植物抗逆反应中发挥着重要作用。文中从胡杨cDNA克隆到2个甜菜碱醛脱氢酶基因,分别命名为PeBADH1和PeBADH2。PeBADH1和PeBADH2均编码503个氨基酸的蛋白质,预测分子量分别是54.93 kDa和54.90 kDa。组织表达模式分析发现这2个基因在正常生长、盐和H2O2胁迫下,在不同组织中的表达模式有较大差异。在大肠杆菌中表达并纯化了2个基因的重组蛋白。酶活性分析显示PeBADH1和PeBADH2蛋白对底物的活性分别是0.073μmol/(min.mg)和0.107μmol/(min.mg)。热力学稳定性分析显示这2个蛋白的热力学稳定性具有明显差异。因此,基因表达模式差异与蛋白质酶学性质的不同预示着这2个基因可能存在功能上的分化。     

口蹄疫病毒3A基因在大肠杆菌中的高效表达

将口蹄疫病毒(Foot\|and\|Mouth Disease Virus,FMDV)的3A基因克隆到线形化的原核表达载体pProEX\|HTb中,转化大肠杆菌BL21和DH5α,经氨苄抗性筛选得到阳性克隆,IPTG诱导表达。SDSPAGE和West bolt结果证实大肠杆菌菌体不可溶性蛋白中富含3A蛋白,说明3A蛋白在表达产物中以包涵体的形式存在,所表达的蛋白含量占菌体蛋白的29.2%。     

Pyrosequencing Reveals Contrasting Soil Bacterial Diversity and Community Structure of Two Main Winter Wheat Cropping Systems in China

Microbes are key components of the soil environment, playing an important role in maintaining soil health, sustainability, and productivity. The composition and structure of soil bacterial communities were examined in winter wheat–rice (WR) and winter wheat–maize (WM) cropping systems derived from five locations in the Low-Middle Yangtze River plain and the Huang-Huai-Hai plain by pyrosequencing of the 16S ribosomal RNA gene amplicons. A total of 102,367 high quality sequences were used for multivariate statistical analysis and to test for correlation between community structure and environmental variables such as crop rotations, soil properties, and locations. The most abundant phyla across all soil samples were Proteobacteria, Acidobacteria, and Bacteroidetes. Similar patterns of bacterial diversity and community structure were observed within the same cropping systems, and a higher relative abundance of anaerobic bacteria was found in WR compared to WM cropping systems. Variance partitioning analysis revealed complex relationships between bacterial community and environmental variables. The effect of crop rotations was low but significant, and interactions among soil properties, locations, and crop rotations accounted for most of the explained variation in the structure of bacterial communities. Soil properties such as pH, available P, and available K showed higher correlations (positive or negative) with the majority of the abundant taxa. Bacterial diversity (the Shannon index) and richness (Chao1 and ACE) were higher under WR than WM cropping systems.     

不同批号蕲蛇酶在家兔血液凝固系统上的生物活性检测

目的：研究不同批号蕲蛇酶静脉给予家兔后,对血液凝固系统各项指标的影响,以判定其药效的稳定性。方法：取家兔,纯白色,体重1．5－2．5kg,雌雄兼用,每日静脉注入蕲蛇酶1．0u/kg.d^-1,连用3－5天,药前、药后从心脏取血6ml,取全血1ml作血栓形成;余血以3．0％枸橼酸钠按1：9抗凝,分离富血小板血浆（PRP）,测定其血小板数目和血小板聚集率,以贫血小板血浆（PPP）测定凝血酶时间（TT）,凝血酶原时间（PT）,部分凝血活酶时间（KPTT）以及纤维蛋白原（Fg)含量。结果：5个批号的蕲蛇酶药后3天或5天均可明显使血栓形成的重量减轻,长度缩短,Fg含量减少（P＜0．01）,TT,PT,KPTT均延长（P＜0．05－0．01）,血小板数轻度减少,聚集率抑制达20％－50％,结论：不同批号的蕲蛇酶静脉给予家兔,具有显著的作用于血液凝固系统,导致血栓形成减少,表明对心脑血管内血栓形成药学相同,说明用家 兔作为鉴定药品质量是可行而必须。     

Identification and characterization of a novel salt‐tolerant esterase from a Tibetan glacier metagenomic library

A salt‐tolerant esterase, designated H9Est, was identified from a metagenomic library of the Karuola glacier. H9Est gene comprised 1071 bp and encoded a polypeptide of 357 amino acids with a molecular mass of 40 kDa. Sequence analysis revealed that H9Est belonged to the family IV of bacterial lypolitic enzyme. H9Est was overexpressed in Escherichia coli and the purified enzyme showed hydrolytic activity towards p‐nitrophenyl esters with carbon chain from 2 to 8. The optimal esterase activity was at 40°C and pH 8.0 and the enzyme retained its activity towards some miscible organic solvents such as polyethylene glycol. A three‐dimensional model of H9Est revealed that S200, D294, and H324 formed the H9Est catalytic triad. Circular Dichroism spectra and molecular dynamic simulation indicated that the esterase had a wide denaturation temperature range and flexible loops that would be beneficial for H9Est performance at low temperatures while retaining heat‐resistant features. © 2015 American Institute of Chemical Engineers Biotechnol. Prog., 31:890–899, 2015