O139霍乱弧菌检测方法的研究─诊断血清的制备

本文以Ｏ１３９死菌免疫健康家兔,经吸收去除非特异性凝集素制成的特异性诊断血清,专供诊断霍乱弧菌Ｏ１３９之用。采用玻片凝集试验对５株Ｏ１３９菌株及１２６株肠道菌进行验证,在敏感性和特异性方面均获得满意的结果。     

中国汉族人群间-α-胰蛋白酶抑制因子(ITI)的遗传多态性

我们建立了测定间-α-胰蛋白酶抑制因子遗传表型的聚丙烯酰胺凝胶等电聚焦免疫固定技术,应用这种方法对居住在成都地区的汉族群体进行了群体研究和家系调查,结果表明中国汉族人群间-α-胰蛋白酶抑制因子具有遗传多态性,它有希望成为法医血液遗传学新的遗传标记。     

烟酸转磷酸核糖激酶和丙酮酸羧化酶共表达对大肠杆菌BA002产丁二酸的影响

大肠杆菌BA002是敲除了乳酸脱氢酶的编码基因 (ldhA) 和丙酮酸-甲酸裂解酶的编码基因 (pflB) 的工程菌。厌氧条件下NADH不能及时再生为NAD+,引起胞内辅酶NAD(H)的不平衡,最终导致厌氧条件下菌株不能利用葡萄糖生长代谢。pncB是烟酸转磷酸核糖激酶 (NAPRTase) 的编码基因,通过过量表达pncB基因能够提高NAD(H)总量与维持合适的NADH/NAD+,从而恢复了厌氧条件下重组菌E. coli BA014 (BA002/pTrc99a-pncB) 的生长和产丁二酸的性能。然而,BA014在厌氧发酵过程中有大量丙酮酸积累,为进一步提高菌株的丁二酸生产能力,减少副产物丙酮酸的生成,共表达NAPRTase和来自于乳酸乳球菌 NZ9000中丙酮酸羧化酶 (PYC) 的编码基因pyc,构建了重组菌E. coli BA016 (BA002/pTrc99a-pncB-pyc)。3 L发酵罐结果表明,BA016发酵112 h后,共消耗了35.00 g/L的葡萄糖。发酵结束时,菌体OD600为4.64,产生了25.09 g/L丁二酸。通过共表达pncB和pyc基因,使BA016的丙酮酸积累进一步降低,丁二酸产量进一步提高。     

作物抗除草剂转基因研究进展

综述了抗除草剂基因研究的意义、研究机理及国内外研究现状,分析了各种转基因方法的优缺点,展望了除草剂抗性育种的发展方向。     

棘托竹荪乙酸乙酯提取物的化学成分研究

用乙酸乙酯对棘托竹荪进行常温和80℃高温提取,得率为2.11%,3.79%,应用GC-MS对提取物的化学成分进行研究,用FFAP柱分离,质谱法鉴定出58种成分,其主要成分为：有机酸、酮、酯、倍半萜、杂环化合物,醛,酚,胺等。     

Characterization and Ectopic Expression of a Populus Hydroxyacid Hyd roxyci n nam oylt ra nsferase

Cutinized and suberized cell walls in plants constitute physiologically important environment interfaces. They act as barriers limiting the loss of water and nutrients and protecting against radiation and invasion of pathogens. The roles of cutin- and suberin polyesters are often attributed to their dominant aliphatic components, but the contri- bution of aromatic composition to their physiological function remains unclear. By functionally screening a subset of Populus trichocarpa BAHD/HXXXD acyltransferases, we identified a hydroxycinnamoyltransferase that shows specific transacylation activity on ~0-hydroxyacids using both feruloyl- and p-coumaroyl- CoA as the acyl donors. We named this enzyme P. trichocarpa hydroxyacid/fatty alcohol hydroxycinnamoyltransferase 1 （PtFHT1）. The ectopic expression of the PtFHT1 gene in Arabidopsis increased the incorporation of ferulate in root and seed suberins and in leaf cutin, but not that of p-coumarate, while the aliphatic load in both suberin and cutin polyesters essentially remained unaffected. The overaccumulation of ferulate in lipophilic polyester significantly increased the tolerance of transgenic plants to salt stress treatment; under sub-lethal conditions of salt stress, the ratios of their seed germination and seedling establishment were 50% higher than those of wild-type plants. Our study suggests that, although aromatics are the minor component of polyesters, they play important role in the sealing function of lipidic polymers in planta.     

一株产纤维素酶细菌的分离鉴定及酶学特性研究

从采集的含腐烂树叶的土壤中,筛选到1株产纤维素酶能力较高的菌株JJ-3,经16S r RNA基因序列分析,鉴定该菌株为产酸克雷伯氏杆菌(Klebsiella oxytoca)。产酶条件及酶学特性研究表明:以滤纸为碳源、蛋白胨为氮源、初始p H为8.0的培养基中发酵3 d更利于纤维素酶的合成;菌株发酵液在中性和碱性条件下均有较高的滤纸酶活力,分别可达118.7 U/m L(p H7.0),167.8 U/m L(p H8.0)和120 U/m L(p H9.0);所产纤维素酶的最适酶反应p H为7.0,最适酶反应温度为40℃,对温度比较敏感,在p H7.0-8.0的范围内具有较好的稳定性,能满足中性和碱性纤维素酶的要求。