西方蜜蜂Lozenge基因的克隆鉴定及时空表达分析

Lozenge蛋白（Lz蛋白）是昆虫的重要转录因子,在昆虫胚胎发育过程中发挥重要作用。为研究Lozenge在西方蜜蜂Apis mellifera中的作用,本研究克隆了Lozenge基因,并对其进行生物信息学分析,同时基于荧光定量PCR技术检测该基因在西方蜜蜂不同发育时期（卵期、幼虫期、蛹期和成年蜂）和10日龄哺育蜂各组织的表达谱。生物信息学分析结果显示,Lozenge基因的开放阅读框（ORF）为1 554 bp,共编码517个氨基酸,预测分子量为54.63918 kDa,等电点为6.08;结构域预测分析发现Lozenge蛋白含有一个Runt结构域,多物种蛋白序列对比发现该蛋白同源性高。时期表达谱表明,该基因在第1日卵和第2日卵的表达量远高于其他时期,在卵期表达量随时间依次递减,幼虫期表达量极低,蛹期表达量呈先增后减的趋势,而成年蜂中均有表达;组织表达谱显示,该基因在哺育蜂头部、上颚腺中的表达量较高,而在腹部的表达量低。这些结果表明,Lozenge基因可能在西方蜜蜂胚胎期细胞发育过程、哺育蜂蜂王浆合成和分泌过程中发挥重要作用,这些结果为该基因功能的深入研究提供了重要的理论参考。     

Molecular Cloning and Characterization of Transferrin from Wax Moth, Galleria mellonella

Complete mRNA sequence of transferrin from Galleria mellonella was obtained, and compared with those of other species. Until now, two types of insect transferrin were reported. Transferrins in cockroach and termite have two iron binding sites while those in most other insect groups, studied for the protein, have only one. It was suggested that the presence of two types of transferrin was related with transferrin evolution, because vertebrate transferrins have two iron binding sites, called N and C terminal lobe. It was shown that G. mellonella transferrin also has only one iron binding site (N terminal lobe), and the deduced amino acid sequence was most similar to those of Manduca sexta and Bombyx mori.     

Immune-Enhancing Activity Screening on Extracts from Two Crickets, Gryllus bimaculatus and Teleogryllus emma

This study was performed to explore novel and valuable uses of insect resources, important subjects of the natural compound used in bio‐industries. The whole bodies of two crickets, Gryllus bimaculatus and Teleogryllus emma, selected from medicinal insect species, were carefully ground and treated with 80% EtOH. The insect extracts were solubilized and separated by hexane, butanol, and D.W according to their polarities. Three types of extracts, a D.W fraction (G1) and a boiling extract (G2) of an introduced cricket, G. bimaculatus, and a D.W fraction (T1) of a Korean local cricket, T. emma, were prepared to assay immune stimulating activity of cricket originated compounds. The all of three treated cricket extracts showed to increase IL‐4, IFN‐, and TNF‐α. Among those extract, extract G2, boiled extract from G. bimaculatus, was the best immune–enhancing fraction. The results of this study could be fundamental information for further works to use insects as natural resources having plenty of potentials and varieties.     

Crystal structure of Streptomyces diastaticus No. 7 strain M1033 xylose isomerase

The crystal structures of Streptomyces diastaticus No. 7 strain M1033 xylose isomerase (SDXyI) have been analysed and refined at 0.19nm. The crystal space group is I222, with unit cell dimensions of a=9.884 ran, b=9.393nm and c=8.798nm. Based on the coordinates of the Streptomyces rubiginosus xylose isomerase (SRXyI), the initial model of SDXyl was built up by the dose packing analysing and R-factor searching and refined by PROLSQ to a final R-factor of 0.177 with the rms deviations of bond lengths and bond angles of 0.001 9nm and 2.1°, respectively. No significant global conformation change existed between SRXyI and SDXyI except the local conformation in the active site.     

含吸氢酶基因（hup）嵌合质粒的构建和吸氢酶活性在阴沟肠杆菌中的表达

以质粒ｐＲＫ４０４为载体亚克隆含大豆根瘤菌吸氢酶结构基因（ｈｕｐ）的片段,构建成嵌合质粒ｐＨＲ１１、ｐＨＲ４和ｐＨＲ１０。通过三亲本杂交将这些嵌合质粒导入无吸氢活性的Ｒｈｏｄｏｂａｃｔｅｒｓｐｈａｅｒｏｉｄｅｓ２４１菌株（Ｈｕｐ－）,均获得Ｈｕｐ＋的接合子。利用启动子检测质粒ｐＭＰ２２０证明,在ｈｕｐ对结构基因上游１．２ｋｂ内存在ｈｕｐ启动基因片段。以ｐＲＫ２０１３为助质粒可将ｐＨＲ１１导入Ｅｎｔｅｒｏｂａｃｔｅｒｃｌｏａｃａｅ和Ｋｌｅｂｓｉｅｌｌａｏｘｙｔｏｃａ等土壤固氮菌株。本文以接合子Ｅ．ｃｌｏａｃａｅＥＨ１１１３为例,通过对基因组ＤＮＡＳｏｕｔｈｅｒｎ杂交分析证明,嵌合质粒ｐＨＲ１１在ＥＨ１１１３中稳定贮存和复制。Ｈ２诱导接合子ＥＨ１１１３吸氢酶活性高表达,吸氢活性与放氢活性比值约为对照的两倍。当以延胡索酸为电子受体时,吸氢酶的吸氢作用支持菌株固氮酶活性的提高。     

玉米根微粒体ABA结合蛋白的性质及逆境胁迫的影响

以玉米根微粒体为材料进行的微量放射配体结合（ＭＲＬＢ）实验表明玉米根微粒体膜上存在着ＡＢＡ结合位点,ＡＢＡ与ＡＢＡ结合蛋白（ＡＢＡ－ＢＰ）结合的最适ｐＨ为６．５,结合反应对温度（０℃和２５℃）不太敏感,ＡＢＡ与ＡＢＡ－ＢＰ的结合反应是一个动态平衡过程,５ｍｉｎ即可达最大结合（Ｂｍａｘ）的５０％,３０ｍｉｎ达到最大结合,１ｈ内基本保持不变。胰蛋白酶处理表明此结合位点为蛋白质,冻融实验则表明此蛋白与ＡＢＡ的结合不仅要求其自身具有特定构象而且需要有一定的膜脂环境,ＤＴＴ处理实验结果显示ＡＢＡ－ＢＰ中可能存在着二硫键。逆境处理可以提高玉米根微粒体膜对ＡＢＡ的结合活性,盐胁迫、渗透胁迫、干旱胁迫和热冲激处理分别使结合活性上升３４．９％、１７．８％、２３．１％和１３．３％。     

一个未知的特异结合雌激素效应元件编码链的单链结合蛋白

本文介绍一个不是雌激素受体（ＥＲ）却能专一地结合雌激素效应元件（ＥＲＥ）编码单链的单链结合蛋白,对此蛋白在细胞中的定位、组织中的分布、热稳定性、同二价金属离子的关系作一初步研究。发现其受雌激素负调控。此蛋白在人病理样品２９例乳癌中同ＥＲ的含量似有一定的负相关关系,讨论了上述结果的意义。     

大肠杆菌rpoH基因的克隆,表达及其产物的纯化

本文用ＰＣＲ方法获得大肠杆菌热休克蛋白转录因子σ３２的编码基因ｒｐｏＨ,并克隆在含有ｔａｃ启动子的表达载体ｐＵＨＥ中,经ＩＰＴＧ诱导,在大肠杆菌中表达了Ｃ端融合有６个寡聚组氨酸的σ３２。表达产物经金属螯合层析一步纯化,达到ＳＤＳ－ＰＡＧＥ银染一条带纯度,氨基酸组成分析及Ｎ端序列分析结果与文献报道一致。３５Ｓ细胞内参入实验表明：即使在较低的温度下,表达产物σ３２（Ｈｉｓ）６也能导致热休克蛋白如ＧｒｏＥｌ、ＤｎａＫ、Ｈｔｐ的大量合成．     

广东滩涂经济鱼类寄生吸虫──Ⅳ．独睾科─新属─新种记述（复殖目）

本文对广东滩涂经济鱼类寄生复殖吸虫独睾科ＭｏｎｏｒｃｈｉｉｄａｅＯｄｈｎｅｒ,１９１１中一新属新种;椭囊吸虫属。Ｅｌｌｉｐｔｏｂｕｒｓａｇｅｎ．ｎｏｖ．、单睾椭囊吸虫Ｅｌｌｉｐｔｏｂｕｒｓａｓｉｎｇｌｏｒｃｈｉｓｓｐ．ｎｏｖ．进行了记述。