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21.
Comparative proteome analysis of butachlor-degrading bacteria 总被引:1,自引:0,他引:1
A Pseudomonas putida strain, named ER1, was isolated from an agricultural soil and found to actively degrade the herbicide butachlor. The enzyme
extracted from ER1 could degrade butachlor. Furthermore, incubation of ER1 in a medium containing 50 mg/kg of butachlor after
3 days resulted in the high butachlor-degrading enzyme activity of ER1. Response of ER1 to butachlor might be related to changes
in protein composition at both quantitative and qualitative levels. Total proteins were extracted from control strain (incubated
in the medium without butachlor) and the treated strain (incubated in the medium with butachlor). The proteins were separated
by two-dimensional gel electrophoresis. Of the total number of ER1 protein, 11 spots were significantly changed under butachlor
stress. Analysis by matrix-assisted laser desorption/ionization mass spectrometry and tandem mass spectrometry coupled with
database searching allowed the function of some proteins which were similar to the hydrolases activity or oxidoreductase activity. 相似文献
22.
DNA的简便高效制备方法是研究基因结构、功能及开展其它各项研究的基础。首次报道了针对节旋藻的结构和组成特性而建立的制备节旋藻高分子量DNA的两种方法。其中第一个方法是常规方法,可大量提取纯度较高、分子量达50kb的节旋藻DNA,可用于构建节旋藻质粒库、Southern杂交和PCR操作等;第2种方法是用脉冲电场凝胶电泳分离DNA片段,制备的DNA片段达数百kb,可用于构建节旋藻噬菌体库、粘粒库、BAC库等,从而为构建节旋藻物理图谱,定位克隆基因奠定基础。 相似文献
23.
温度对嗜水气单胞菌蛋白质表达的影响 总被引:3,自引:1,他引:3
嗜水气单胞菌(Aeromonashydrophila)广泛存在于水体中,是水产养殖的重要致病菌。在导致水产养殖业重大经济损失的同时,该菌还可以引起人类急性胃肠炎、败血症等疾病 ,是颇受关注的一种新人畜共患菌。采用现代生物学技术对其进行深入研究具有重要意义。热休克应答最早是在真核生物研究中发现的热诱导基因表达现象,现认为普遍存在于从细菌到高等真核生物的整个生物界。目前 ,研究热休克应答及其基因表达调控的变化主要集中在真核生物领域,而采用蛋白质组学的方法对细菌热休克应答进行研究则少有报道。蛋白质组学是一门新… 相似文献
24.
采用高pH不连续系统聚丙烯酰胺垂直板凝胶电泳,特异性组织化学染色对中华绒螯蟹(Eriocheir sinensis)的血清、肌肉、鳃、心脏、肝胰腺、精巢和精子等组织的乳酸脱氢酶(LDH)同工酶酶谱进行了研究。同时,利用2种底物(乳酸钠和α-羟基丁酸钠)进行了特异性反应,并对其精子特异性乳酸脱氢酶进行了研究。结果表明:以乳酸钠为底物时,中华绒螯蟹的肌肉、鳃、血清和心脏有2条谱带,而精巢和精子有3条谱带,但在肝胰腺中未发现谱带;以α-羟基丁酸钠为底物时,只在血清、精巢和精子发现有1条谱带。从而说明,中华绒螯蟹乳酸脱氢酶同工酶存在组织特异性;精子存在特异性乳酸脱氢酶。 相似文献
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27.
采用聚丙烯酰胺垂直板梯度凝胶电泳技术,对管角螺7种组织(外套膜、肌肉、肝脏、心脏、生殖腺和缠卵腺)的5种同工酶(EST、SOD、ME、MDH、LDH)进行了分析,结果表明:5种同工酶存在不同程度的组织特异性,SOD、EST、LDH在肝脏组织中有较高活性,而MDH、ME在心脏组织中活性较高。 相似文献
28.
Spatial heterogeneity in a deep artificial lake plankton community revealed by PCR-DGGE fingerprinting 总被引:1,自引:0,他引:1
To explore the spatial heterogeneity of plankton communities in a deep artificial lake(Songhua Lake,China),samples were collected at seven sites. Samples were investigated by denaturing gradient gel electrophoresis(DGGE) analysis of the PCR-amplified 16 S and 18 S r RNA genes and specif ic bands were sequenced. Cluster analysis of the DGGE profiles revealed that all of the samples grouped into two distinct clusters,in accordance with sampling site; while in each cluster,the divergence of sub-clusters correlated with sampling depth. Sequence analysis of selected dominant DGGE bands revealed that most sequenced phylotypes(84%) exhibited ≥97% similarity to the closest sequences in Gen Bank,and were affiliated with ten common freshwater plankton phyla(Proteobacteria,Actinobacteria,Bacteroidetes,Cyanobacteria,Bacillariophyta,Pyrrophyta,Cryptophyta,Ciliophora,Stramenopiles,and R otifera). Several of these groups are also found worldwide,indicating the cosmopolitan distribution of the phylotypes. The relationships between DGGE patterns and environmental factors were analyzed by redundancy analysis(RDA). The results suggested that,total nitrogen,nitrate,nitrite,ammonia,and CODM n concentrations,and water temperature were strongly correlated with the variation in plankton composition. 相似文献
29.
海洋动物粪土是南极陆地生态系统养分的重要来源,粪土层细菌群落对南极苔原碳、氮循环过程起重要作用,但目前对南极海洋动物粪土层中细菌群落的变化特征却鲜有报道。本文采集了东南极四个企鹅、海豹粪土剖面样品,通过酶活性、微生物量碳、微生物熵、土壤呼吸和DNA浓度测定以及16 S r DNA-DGGE分析,探讨了粪土层中细菌群落变化特征及其与环境因子的关系。土壤转化酶、脲酶和磷酸酶活性、微生物量碳、土壤呼吸和微生物熵随深度增加而递减,而代谢熵增加,表明随深度增加,微生物生存环境恶劣,造成细菌丰度和酶分泌量减小,需更多有机碳进行能量代谢。土壤DNA浓度与pH、含水率、TOC、TN、微生物量碳、土壤呼吸以及酶活性呈高度正相关,表明这些因子对粪土层中细菌种群的丰度有重要影响。DGGE图谱分析证实:东南极海洋动物粪土中含丰富的细菌群落结构,随深度增加泳道带型数量和亮度递减,表明细菌多样性和丰度递减。聚类分析表明:四个剖面随深度泳道带型差异明显,细菌遗传相似性为46%,企鹅、海豹粪土细菌群落差异性尤为明显;发现四个粪土剖面中,细菌丰度与企鹅、海豹粪的相对含量呈协调一致性变化,且表层5cm粪土层细菌丰度最高,表明东南极企鹅和海豹排泄物对土壤中细菌群落多样性变化起重要作用。 相似文献
30.
Previous genetic studies on perch (Perca fluviatilis L.) in northern and southern regions of Europe have shown low heterozygosity. No such investigation has been conducted in the central part of Europe. The genetic variability ofP. fluviatilis in four Swiss lakes (Lake Constance, Lake Zürich, Lake Geneva and Lake Maggiore) was investigated. These four lakes belong to three different drainage systems (Rhine, Rhone and Po) without connections. A total of 136 fish were analysed electrophoretically. Only one locus (SOD
*) was highly polymorphic in Lake Constance among the 27 loci studied. The expected heterozygosities for each population and for the total population were higher than in the previous studies but low (H
S= 0.38–2.7%;H
T=1.22%) and Nei's genetic distances were small (0.000–0.003). However, the jack-knifed mean of the Wright'sF
STwas calculated as 0.142, which indicates modest genetic differentiation among the perch populations in Switzerland, due to the differentiated population in Lake Constance. 相似文献