降解甲醛的假单胞菌菌株的固定化研究

从印染厂采集的活性污泥中筛选得到1株快速降解甲醛的菌株并命名为 W1,通过形态与生理生化特征的鉴定,初步鉴定 W1菌株为假单胞菌属(Pseudomonas)．以海藻酸钠为包埋载体固定 W1菌株进行降解甲醛的初步研究,采用不同海藻酸钠浓度、菌悬液添加量配制成不同的包埋载体,利用 L9(33)正交试验对 W1菌株降解甲醛条件进行优化,分析其甲醛降解率的变化．实验结果表明：培养基为(NH4)2 SO42．4 g/L, MgSO4?7H2 O 0．2 g/L,微量元素母液0．1 mL,pH 值9．0,30℃恒温培养,在此条件下甲醛48h内的降解率达80．3％．通过对甲醛降解菌 W1固定化的研究,为生物法去除甲醛的应用奠定基础．     

类产碱假单胞菌谷氨酸脱氢酶酶学性质的研究

类产碱假单胞菌的谷氨酸脱氢酶水平受氮源调节,以氮为唯一氮源时酶水平有明显提高,研究表明,该酶的最适反应温度为５０℃,催化氢化反应和脱氨反应的最适ｐＨ值分别为８．０和８．８,金属离子及嘌呤核苷酸对酶活力的影响不显著。     

红罗非鱼"突眼病"病原的初步研究

从患“突眼病”的红罗非鱼眼球中分离出RT -E980 1菌 ,经人工感染试验确认为致病菌 .该菌大小为 (0 .6～ 1.0 ) μm× (1.3～ 2 .8) μm ,短杆状 ,单个、成对或链状 ,端生 3～ 4根鞭毛 ,革兰氏染色阴性 ,无芽孢 ,氧化葡萄糖产酸、不产气 ,氧化酶、过氧化氢酶试验阳性 ,MR、VP、H2 S反应阴性 ,能在SS、麦康凯培养基上生长 ,认为该菌系假单胞菌属(Pseudomonas)的种类 .药敏试验表明该菌对氟哌酸、环丙沙星、氟嗪酸、丁胺卡那霉素、庆大霉素、新霉素等敏感 .     

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。     

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.     

荧光假单胞菌的应用与展望

植物根际促生菌(PGPR)中的荧光假单胞菌(Pseudomonas fluorescens)对植物病原体具有潜在的拮抗作用,同时具有促进植物生长的能力.阐述了荧光假单胞菌在实际生产中的应用潜力.荧光假单胞菌可以通过产生生长素,增强土壤中磷、钾的可用性,促进植物叶绿素含量的增加,及产生谷胱甘肽、ACC脱氨酶等形式促进植物的生长.通过产抗生素(吩嗪、2,4-二乙酰基间苯三酚、藤黄绿脓菌素、硝吡咯菌素)、拮抗线虫等方式帮助植物体抵抗病虫害的侵袭.除此之外,荧光假单胞菌所具有的定殖与产铁载体能力在植物的促生与抗病方面皆发挥着重要作用.荧光假单胞菌在农业生产方面具有巨大的应用潜力.     

一株铜绿假单胞菌的溶磷特征及其对底泥中Pb的固定化

通过纯培养和模拟实验研究一株铜绿假单胞菌JM1对磷酸钙的溶解特征及其对底泥中Pb的固定化作用. 结果表明: 菌株JM1对磷酸钙和磷酸铝均具有溶解作用, 96 h内释放的溶解性正磷酸盐的质量浓度分别为240.63,92.73 mg/L, 培养液pH值分别下降至464,512, 菌株JM1还可以利用卵磷脂进行生长但不释放磷酸根离子; 菌株JM1使灭菌底泥与不灭菌底泥中固定化Pb的质量比分别增加至14.02,11.83 mg/kg, 即菌株JM1对底泥中的Pb具有较强的固定能力.     

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。