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61.
X射线荧光光谱仪测定地质样品中的23个常量元素和微量元素,采用粉末压片法,测量范围常量元素从0.0026%到90.36%;微量元素从0.094ug/g到1900ug/g。该方法具有简便、快速、准确等优点。 相似文献
62.
一株原油降黏细菌的筛选 总被引:8,自引:0,他引:8
自环境中分离出一株假单胞菌,在厌氧条件下能显著降低高黏度原油黏度,降黏率最高可达68%,气相色谱显示,降解前后原油中各组份含量发生显著变化。 相似文献
63.
抑制姜瘟青枯假单胞菌的木霉菌株的筛选及其抑菌机理 总被引:15,自引:1,他引:15
筛选得到一株可有效抑制姜瘟青枯假单胞菌的木霉菌株SMF2(Tricoderma spp SMF2),证实其胞外分泌的抗生素--木霉素是抑制姜瘟菌生长的主要物质,该物质对热稳定,固体发酵是培养木霉制剂的有效方法,并对培养基的组成、培养条件进行了初步优化。 相似文献
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66.
Isolation,purification and characterization of a new organphosphorus hydrolase OPHC2 总被引:1,自引:0,他引:1
WUNingfeng DENGMinjie SHIXiuyun LIANGGuoyi YAOBin FANYunliu 《科学通报(英文版)》2004,49(3):268-272
A bacterium with the capability of degrading organphosphorus, identified as Pseudomonas pseudoaicaligenes, is isolated from OP-treated soil. The organphosphorus hydrolase OPHC2 from this bacterium has been purified and characterized. OPHC2 has optimum activity for the reaction at 65℃ and pH 9.0 with methyl parathion as a substrate, it also shows good thermal and pH stability. Most metal ions and chemicals have no effect on the activity of OPHC2. The analyses of nucleotide sequence encoding OPHC2 and amino acid sequence of OPHC2 show that there are lower homologies with those of organphosphorus hydrolase reported in GenBank. 相似文献
67.
Dynamics of proteins in Golgi membranes: comparisons between mammalian and plant cells highlighted by photobleaching techniques 总被引:5,自引:0,他引:5
In less than a decade the green fluorescent protein (GFP) has become one of the most popular tools for cell biologists for the study of dynamic processes in vivo. GFP has revolutionised the scientific approach for the study of vital organelles, such as the Golgi apparatus. As Golgi proteins can be tagged with GFP, in most cases without altering their targeting and function, it is a great substitute to conventional dyes used in the past to highlight this compartment. In this review, we cover the application of GFP and its spectral derivatives in the study of Golgi dynamics in mammalian and plant cells. In particular, we focus on the technique of selective photobleaching known as fluorescence recovery after photobleaching, which has successfully shed light on essential differences in the biology of the Golgi apparatus in mammalian and plant cells. 相似文献
68.
GFP标记的GDNF重组腺病毒载体的构建和体内外表达 总被引:2,自引:0,他引:2
通过构建绿色荧光蛋白(GFP)和胶质细胞源性神经营养因子(GDNF)共表达的腺病毒载体,讨论其在治疗脊髓和脑有关神经系统疾病的潜在应用价值,了解腺病毒载体在大鼠体内的分布及在体外分泌外源基因产物能力,并对其生物安全性作了初步考察,为GDNF重组腺病毒载体在临床和基础研究中的应用作了一定准备. 相似文献
69.
ZHAO HuaBing LI YongJun CHEN Wei CAI BaoLi 《科学通报(英文版)》2007,52(14):1942-1948
A novel salicylaldehyde dehydrogenase involved in catabolism of naphthalene from Pseudomonas putida ND6, NahV, has been identified. NahV exhibited lower identity in amino acid sequence with the classic salicylaldehyde dehydrogenase, NahF, from P. putida ND6. This is the first report of an isofunctional enzyme of bacterial salicylaldehyde dehydrogenase. Comparison of Km and Vmax values of NahV and NahF demonstrated that NahF has a more efficient catalytic reaction than NahV, while NahV has much higher affinity for salicylaldehyde and NAD^+. Both enzymes exhibited broad substrate specificities and catalyzed the oxidation of salicylaldehyde, 5-chlorosalicylaldehyde, formaldehyde, m-nitrobenzaldehyde, o-nitrobenzaldehyde, o-methoxybenxaldehyde, glutaraldehyde, caprylic aldehyde, and glyoxal. However, the relative rates at which the substituted analogs are transformed differ considerably. NahV activity could be enhanced by Fe^2+, Cu^2+ and Zn^2+; whereas NahF activity could only be stimulated by Fe^2+, NahF is more stable than NahV at elevated temperatures. Dot-blot hybridization analyses showed that nahF-like genes occurred in all naphthalene-degradation bacteria isolated in this study, whereas nahV-like genes were present in only some naphthalene-degrading bacteria. 相似文献
70.
IntroductionPolyhydroxyalkanoates (PHAs)areafamilyofintracellularbiopolymerssynthesizedbymanybacteriaasintracellularcarbonandenergystoragecompounds[1] .PHAshaveawiderangeofphysicalpropertiesrangingfrombrittletoflexibletoelastic ,dependingontheirmonomerstr… 相似文献