大亚湾海洋细菌Pseudomonas sp.中的红色素

海洋细菌Pseudomonas sp.，采集于大亚湾，从该菌的菌体提取物分离得到2个红色素：灵菌红素A和新的衍生物二甲基灵菌红素B。它们的结构通过NMR，LC-MS等确定，并得出灵菌红素是具有强烈抗微生物和细胞毒性的化合物，同时研究了它的培养条件。     

铜绿假单胞菌液体发酵产生絮凝现象的研究

对铜绿假单胞菌液体发酵产生的絮凝现象进行了研究。初步确定其由铜绿假单胞菌产生的生物膜引起,测得生物膜中多糖含量约为6.3%,蛋白质含量约为7.7%。考察了添加颗粒营养物质豆饼粉对絮凝现象的影响,分析了天然群体感应抑制剂水杨酸、丁香酚、儿茶素、姜黄素和大蒜提取物对生物膜和菌浓的影响以及群体感应淬灭酶对菌浓的影响。结果显示,添加颗粒营养物质对絮凝物影响不显著;天然群体感应抑制剂不能显著提高铜绿假单胞菌液体发酵菌浓,但对生物膜的分散具有一定作用;群体感应淬灭酶对铜绿假单胞菌液体发酵浓度无显著影响。     

Pseudomonas putida KT2442制备中长链聚羟基烷酸酯

初步探讨了利用Pseudomonas putida KT2442制备中长链聚羟基烷酸酯(MCL-PHAs)的工艺,考察了不同碳源对菌体生长和产物合成的影响.在2.5 L发酵罐上采用高密度细胞培养制备以油酸为碳源,细胞干重达120g/L,MCL-PHAs质量浓度达40g/L,产物质量分数为34%,生产速率为0.965 g·L-1·h-1;以玉米油水解物为碳源,细胞干重达105g/L,MCL-PHAs达28g/L,产物质量分数为26.5%,生产速率为0.667 g·L-1·h-1.以玉米油水解物为碳源所得细胞浓度、产物浓度与以油酸为碳源所得结果比较接近,有利于降低生产成本.     

Studies on Locusts‘ Pathogenesis and Energy Metabolic Inhibition Induced by the Insecticidal Protein Purified from Pseudomonas Pseudoalcaligenes

The insecticidal protein produced by Pseudomonas pseudoalcaligenes is purified from the suspension of the bacterial culture. As an intact molecule, the protein acts on the foregut, midgut, hindgut, vasa Malpighii and fat body, and kills locusts. The disinsection rates of feeding and injection are 63.3% and 65.7%, respectively. After 24h to 48h, it is observed that all these tissues and cells show pathological changes in varying degrees, and so did the host cellular organs of these cells, such as cytoblast, mitochondria, endoplasmic reticulum and ribosome. Particularly, the changes of the mitochondria are much more serious than those of others. Detection of oxygen electrode shows the efficiency of oxidative phosphorylation and the ATP synthesis decreases, while the activity of mitochondrial ATPase is almost not affected. That means the energy utilization of locusts is in gear, but the shortage of the supplying of energy results in their death. This research forms the substantial basis for controlling locusts.     

不动杆菌与假单胞菌对17β-雌二醇的协同降解特性

分别用纯培养与模拟培养法考察不动杆菌LM1与假单胞菌LY1组成的复合菌对17β-雌二醇(E2)的协同降解特性.结果表明:当细胞数量比为1时,复合菌对E2的降解率分别为菌株LM1和LY1单独作用的2.2倍和2.6倍,降解过程中菌株LM1和LY1的细胞数量比趋于1;在28℃,150r/min条件下培养7d后,复合菌对初始质量浓度为1,5,10,20mg/L的E2降解率分别为99.6%,97%,93%,85%;当培养基中氯化钠添加的质量分数为3.5%时,复合菌对E2的降解率显著下降(p0.05);在25℃时复合菌对鸡粪、猪粪及土壤样品中E2的降解率分别为对照组的2.7,3.0,2.8倍.即由菌株LM1和LY1组成的复合菌可通过协同作用降解E2.     

处理油田含聚废水的微生物研究

在油田普遍采用聚合物驱三次采油新技术的同时也产生了含聚丙烯酰胺（PAM）污水的处理问题。含PAM污水的特点是粘度大、含油多、乳化油稳定,故传统的废水处理方法及设施难以使该污水处理达到回注水水质的标准。对模拟含聚废水驯化的好氧颗粒污泥内微生物的研究将有助于油田含聚废水生物处理技术的开发。采用人工模拟油田含聚废水在实验室内驯化好氧颗粒污泥,结果表明好氧颗粒污泥对含聚驱采出水有良好的适应性。在水力停留时间为144h时,好氧颗粒污泥可以将进水中的聚丙烯酰胺由350mg/L降低至150mg/L,去除率达到57％。对颗粒污泥内的优势微生物研究表明,在模拟含聚废水中对PAM起主要降解作用的微生物为产碱假单胞菌。     

Genetics of toxin production and resistance in phytopathogenic bacteria

Genes for phytotoxin production have been identified and cloned from several phytopathogenic pseudomonads. These genes comprise physically linked clusters that have been located both on the chromosome and on endogenous plasmids. Contained within these genetic regions are resistance genes specific to those toxins that have a bactericidal component to their activity. DNA sequences required for toxin production are often conserved among bacteria with divergent host specificities, suggesting the ability of toxin genes to be transferred between bacteria. Toxins are usually modulators of plant pathogenicity, their production causing a significant increase in disease severity. In one case, however, toxin production appears to be a major contributor to the basic pathogenicity of a plant pathogenic bacterium.     

假单胞菌Hy—1对多房棘球蚴泡块的抑制作用

从成都土壤中分离到一株假单胞菌,编号Hy—1。该菌株为革兰氏阴性需氧短杆菌,具极生丛鞭毛,营呼吸代谢,化能异养;还具有能分解Twccn60,液化明胶,不水解淀粉,产生聚—B—羟基丁酸盐颗粒(PHB)等特性。该菌株的代谢产物对一些革兰氏阳性细菌有较强拮抗作用。Hy—1菌苗对小白鼠多房棘球蚴移植泡块有显著抑制作用,能阻止多房棘球蚴在鼠体内的生长,发育和扩散。初步毒理试验发现Hy—1 对小鼠无急性毒性作用,在体内无存活扩散现象。     

北京地区动物实验设施动物饮水无菌检测 及绿脓杆菌污染菌株鉴定

摘要: 目的了解北京地区动物实验设施动物饮水微生物控制状况。方法根据实验动物无菌动物生活环境国家 标准检测方法,对实验动物设施内的动物饮用水样品进行分离培养。扩增分离绿脓杆菌的16SrRNA,并进行测序, 绘制发育树。结果在27 个参与检测的单位中,未经过处理的饮水无菌生长率41% ; 经过处理的饮水无菌生长率 仅29% 。绿脓杆菌检出率30% ,主要为RHH13 和ZAQ22 两个菌株。结论本次检测的实验动物饮水在处理后的 效果普遍不甚理想,存在绿脓杆菌的污染,直接影响实验动物质量。