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1.
基于pufM基因的乌梁素海富营养化湖区好氧不产氧光合细菌系统发育多样性分析 总被引:3,自引:0,他引:3
好氧不产氧光合细菌(AAPB)的多样性在海洋中已经广泛研究,但在富营养化湖泊中却研究甚少。通过构建和分析AAPB光合中心合成中的关键基因pufM克隆文库,以期揭示乌梁素海富营养化湖区AAPB分布及其系统发育多样性,探讨其在富营养化湖泊中的功能和作用。对乌梁素海红圪卜湖区水体文库中的52个克隆子进行分析,产生了28个OTU,文库覆盖度达到71.4%,反映出文库有较好的代表性。同源性和系统发育分析结果表明,乌梁素海红圪卜湖区AAPB有较高的多样性,与我们之前所发现的同一湖区总细菌多样性较低形成鲜明对比。所获得的序列分属7个亚群,即γ-Proteobacteria(44.2%,含Group-1,-2和-3共3个亚群)、β-Proteobacteria(21.2%)、Rhodobacter-like(7.69%)及2个未知亚群unknown Group-1(21.2%)和Group-2(5.77%)。其中γ-Proteobacteria占到总克隆的44.2%,在低盐的乌梁素海环境中出现高比例的γ-Proteobacteria之前并未见类似报道,并且乌梁素海中存在一些可能是富营养化湖泊特有的AAPB。这表明AAPB可能在富营养化湖泊生态系统的维持和稳定中有重要作用。 相似文献
2.
浑善达克沙地生物土壤结皮及其下层土壤中好氧不产氧光营养细菌群落结构及多样性 总被引:1,自引:0,他引:1
【目的】揭示浑善达克沙地不同类型生物土壤结皮(Biological soil crusts,BSCs)及其下层土壤好氧不产氧光营养细菌(Aerobic anoxygenic phototrophic bacteria,AAPB)群落结构及多样性。【方法】利用Illumina Mi Seq二代高通量测序平台对puf M基因进行测序,使用生物信息学分析方法对序列进行比对分析AAPB的群落结构和多样性。【结果】生物土壤结皮及其下层土壤中,Proteobacteria和Alpha-Proteobacteria是优势门和纲,主要有6个属Bradyrhizobium(9.69%–90.02%)、Brevundimonas(0.83%–16.04%)、Methylobacterium(1.74%–12.56%)、Rhodospirillum(0.91%–32.87%)、Roseiflexus(0.02%–1.79%)和Sphingomonas(0.13%–11.23%);结皮层样品间及下层土壤样品间AAPB种类相似,但丰度有差异;随结皮的发育,结皮层及其下层土壤中AAPB群落多样性升高。【结论】浑善达克沙地BSCs中AAPB群落结构相对复杂,与水体和一般土壤环境中的组成区别明显;AAPB多样性高,且多样性随发育阶段升高而升高,预示着AAPB在荒漠生态系统稳定中有重要的作用。 相似文献
3.
【目的】分析秦皇岛新开河河口及其邻近海域3个站位的细菌多样性,了解入海口污染对微生物多样性的影响,为该海域微生物的生态功能研究提供理论基础。【方法】于2014年8月选取秦皇岛新开河入海河口(XKH)及其邻近海域(W1,W2)共3个站位采集水样,采用荧光显微镜计数以及构建16S rRNA基因克隆文库的方法,分析细菌群落结构多样性与海水环境条件的关系。【结果】邻近海域W1站位的细菌总数(2.62×10~6 cells/m L)和多样性均高于新开河河口XKH站位(细菌总数:6.62×10~5 cells/m L)和W2站位(细菌总数:2.02×10~6 cells/m L);从XKH、W1、W2 3个站位的16S r RNA基因克隆文库中分别获得57、89、87条有效序列,按97%的序列相似性分别划分为46、51、56个OTU,分别属于Proteobacteria、Cyanobacteria、Bacteroidetes、Firmicute、Actinobacteria、Planctomycetes和Verrucomicrobia七个门。其中在XKH和W2站位中,Proteobacteria门的克隆子分别占总克隆数的50.9%和75.9%,是最优势的类群,分属于Alphaproteobacteria、Betaproteobacteria、Gammaproteobacteria、Deltaproteobacteria和Epsilonproteobacteria纲;在W1站位中,Cyanobacteria门的克隆子占总克隆数的38.2%,是该站位的最优势类群,这些优势类群可通过利用水体中的氮等营养来调节水体生态环境。影响细菌群落分布的环境因子主要为溶解氧、p H和氮营养盐。【结论】秦皇岛新开河河口及其邻近海域的细菌具有丰富的多样性,处于河口海域过渡带的水样具有更高的多样性,细菌群落多样性的分布受氮营养盐的影响更为显著。 相似文献
4.
新疆断裂带含硫冷泉泉水细菌群落结构多样性 总被引:2,自引:0,他引:2
摘要:【目的】为了解新疆断裂带含硫冷泉泉水中细菌群落结构的组成和物种多样性。【方法】采用免培养法直接从冷泉水中提取环境总DNA,采用细菌通用引物对泉水中细菌的16S rRNA基因进行PCR扩增,构建16S rRNA基因克隆文库。使用限制性内切酶Hae Ⅲ对随机挑选的阳性克隆子进行限制性片段长度多态性分析(Restriction Fragment Length Polymorphism, RFLP),选出具有不同酶切图谱的序列进行测序、BLAST比对和构建16S rRNA基因系统发育树。【结果】共从细菌16S rRNA基因文库中筛选了228个阳性克隆,RFLP分型得到33个不同的操作分类单元 (Operational Taxonomic Unites, OTUs),覆盖度 (Coverage C) 为92%。BLAST比对、RDP归类及系统发育分析将这33个OTUs归为:变形菌门 (Proteobacteria)、拟杆菌门 (Bacteroidetes) 和厚壁菌门 (Firmicutes)。变形菌门为绝对优势类群,占整个细菌克隆文库的98%,,其中20%左右的类群与硫化物代谢相关的光合自养和化能自养类群纯培养菌具有高的相似性 (>97%)。此外,还发现大量类群 (总文库的64%,其中57%为军团菌属Legionella spp., 类群)与GenBank中已存细菌16S rRNA基因相似性小于96%。【结论】新疆断裂带含硫冷泉泉水中细菌类群的多样性较低,但可能存在大量潜在细菌新种和新分类。另外,该泉水可能是潜在的新军团菌病传播源,因而可能对下游人畜健康存在潜在威胁。 相似文献
5.
新疆艾比湖湿地博乐河入口处土壤细菌多样性分析 总被引:1,自引:0,他引:1
【目的】了解新疆艾比湖湿地国家级自然保护区非培养土壤细菌群落组成及多样性。【方法】采用非培养法直接从湿地土壤提取总DNA进行16S r RNA基因扩增,构建细菌16S r RNA基因克隆文库。使用MspⅠ和AfaⅠ限制性内切酶对阳性克隆进行16S r RNA基因扩增片段的限制性酶切分析(Amplified r DNA restriction analysis,ARDRA),挑取具有不同双酶切图谱的克隆进行测序,序列比对并构建16S r RNA基因系统发育树。【结果】从土壤细菌的16S r RNA基因文库中随机挑取75个不同谱型的克隆子,共得到58个OTUs,系统发育归类为8个细菌类群:绿弯菌门(Chloroflexi)、蓝藻门(Cyanobacteria)、变形菌门(Proteobacteria)、厚壁菌门(Firmicutes)、放线菌门(Actinobacteria)、拟杆菌门(Bacteroidetes)、疣微菌门(Verrucomicrob)和芽单胞菌门(Gemmatimonadetes)。其中,变形菌门为第一优势菌群,拟杆菌门为第二优势菌群,两者约占总克隆的65%。【结论】艾比湖湿地博乐河入口处土壤细菌多样性丰富,且存在一定数量的潜在微生物新种。 相似文献
6.
【目的】了解瘤胃细菌第48家族糖苷水解酶基因(GH48)多样性,为木质纤维素高效降解提供新的基因资源。【方法】通过基因序列比对,设计gh48的简并引物;同时提取两个瘤胃样品的总DNA和总RNA,并将总RNA逆转录成cDNA。以总DNA和cDNA为模板,通过PCR扩增分别建立克隆文库并对克隆文库进行测序;对所得序列进行out种类划分和聚类分析。【结果】本研究共得到了455条编码GH48家族蛋白的基因序列,核苷酸序列之间的相似性为58.65%-100%。对序列的进一步分析表明,89%可以作为区分其种类的界定标准。以此为依据确定所得到的基因序列分别编码66种不同的GH48家族蛋白,分别聚为5个相对独立的类群,其中新类群C中OTU65所代表的序列是cDNA克隆文库中的优势序列,分别占两个cDNA克隆文库的36.4%和19.5%。我们的结果揭示瘤胃细菌gh48基因具有丰富的多样性,同时,其中也存在优势表达的GH48家族蛋白。 相似文献
7.
云南热带户用沼气池的原核生物群落结构研究 总被引:2,自引:0,他引:2
【目的】揭示云南热带农村户用沼气池中的原核生物(细菌和古菌)的群落结构特征。【方法】采用16S r RNA基因克隆文库技术对云南(北)热带代表性气候区的户用沼气池中的原核生物(细菌和古菌)多样性进行研究。【结果】得到细菌330条有效序列,划分为108个OTUs,文库覆盖度为81.5%;古菌有效序列185条,划分为17个OTUs,文库覆盖度为97.8%。通过Gen Bank数据库进行相似性比对与系统发育分析,结果表明:大部分细菌为未知细菌(Unclassified bacteria,占24.19%),优势细菌类群归属拟杆菌门(Bacteroidetes,占23.58%)、绿弯菌门(Chloroflexi,占21.46%)、厚壁菌门(Firmicutes,占13.91%)和变形菌门(Proteobacteria,占8.74%);古菌主要的优势类群为乙酸盐营养型的甲烷八叠球菌目(Methanosarcinales)的鬃毛甲烷菌属(Methanosaeta,占76.75%);此外还检测到少量未培养的泉古菌门细菌(Crenarchaeota,占9.19%)。【结论】云南(北)热带代表性气候区的农村户用沼气池中的微生物种类十分丰富,不同微生物种类的丰度存在明显差异,并存在明显优势种群,且细菌比古菌具有更丰富的多样性。 相似文献
8.
乌梁素海浮游细菌群落结构及其对富营养化因子的响应 总被引:3,自引:0,他引:3
【目的】揭示乌梁素海浮游细菌的群落结构及其对富营养化环境因子的响应,认识乌梁素海浮游细菌多样性,以丰富微生物与富营养化关系的理论。【方法】提取水体浮游细菌总DNA,利用细菌通用引物对63F/1387R进行PCR扩增,构建小口、沙尖北和红圪卜3个湖区16S rRNA基因克隆文库;以典型对应分析(CCA)方法解析浮游细菌群落结构对环境因子的响应。【结果】各湖区中富营养化程度最重的红圪卜位点细菌多样性、丰富度及均匀度最高,而富营养化程度最轻的小口位点细菌多样性、丰富度及均匀度最低。Proteobacteria、Bacteroidetes和Actinobacteria为水体中优势类群。α-、γ-、δ-Proteobacteria,Actinobacteria及Bacteroidetes等菌群丰度随着水体的富营养化程度改变而有显著的变化。各湖区皆存在许多可能具有污染物降解及驱动生源要素循环能力的细菌类群。CCA分析表明TN、NH4+、NO3-和COD等水体指标对浮游细菌群落结构组成的影响较大。此外,乌梁素海水体内未知细菌类群很多;且不同于一般淡水生态系统,乌梁素海中存在9.6%的轻度嗜盐碱性细菌。【结论】乌梁素海水体中浮游细菌多样性较高,细菌群落结构复杂、其类群组成与富营养化因子紧密相关。 相似文献
9.
【目的】菌株MIM37为具有两种光能利用途径的光合异养细菌,分析其基因组和光照对生长的影响,为理解光能利用途径、光营养生物多样性以及光合作用的进化和功能等提供线索。【方法】采用平板涂布划线法分离菌株,结合形态观察及16S rRNA基因和光合基因序列同源性与系统发育分析进行初步分类鉴定;以分光光度法和荧光显微观察法测定光照和黑暗培养下培养液细胞浓度和单细胞体积;构建片段长度为300?500 bp的Illumina PE文库,以Illumina Hiseq2000进行基因组测序,以SOAPdenovo和GapCloser组装序列,以RAST在线软件注释基因组。【结果】从内蒙古腾格里沙漠天鹅湖表层水中分离获得一株细菌MIM37,经16S rRNA基因、pufM和视紫质基因同源性和系统发育分析均显示其与Sphingomonas属亲缘关系最为密切;相对黑暗培养,光照刺激下的最大细胞浓度和单细胞体积大小分别提高了1.2和5.6倍;基因组注释显示MIM37代谢途径多样,含典型好氧菌的呼吸电子传递链,具有完整的好氧不产氧细菌的光合基因簇及xanthorhodopsin-like视紫质蛋白基因,合成铁载体,还原重金属,降解微囊藻毒素和多环芳烃类等。【结论】MIM37属于Sphingomonas属,具有两种光能利用途径,光照可明显促进其生长,多样的代谢模式可能使其在自然环境中极具竞争力、分布广泛并具有应用于修复环境污染的潜力。 相似文献
10.
【目的】研究南海硇洲岛潮汐带栉江珧(Atrina pectinata)样品相关可培养细菌的多样性。【方法】采用纯培养法和基于16S r RNA基因序列的系统发育分析,法对样品中可培养细菌(含放线菌)的类群多样性、物种多样性和遗传多样性进行研究。【结果】用补充0–25%(质量体积比)Na Cl的MA、MH和NA培养基从栉江珧样品中分离到125株细菌。在形态观察和部分生理生化实验结果的基础上去冗余,选取90个代表性菌株进行基于16S r RNA基因序列的系统发育多样性分析。结果表明,这90个分离菌株分属于3个大的系统发育类群(Gamma-proteobacteria、Firmicutes、Actinobacteria)、6个科、10个属,可分为33个物种。优势类群为厚壁菌门(Firmicutes)(56株,62.2%)和γ-变形杆菌亚门(Gamma-proteobacteria)(31株,34.5%)。大多数菌株与其系统发育关系最密切的已知物种的典型菌株之间存在一定的遗传差异(16S r RNA基因序列相似性为95.7%–99.9%),其中有5株可能代表新的分类单元(Potential new taxa)。分析表明,菌株JSM 112024可能代表了盐单胞菌科(Halomonadaceae)的一个属一级新分类单元;菌株JSM 112019、JSM 114045、JSM 114058和JSM 114083可能分别代表盐弧菌属(Salinivibrio)、芽孢杆菌属(Bacillus)、盐单胞菌属(Halomonas)和枝芽孢菌属(Virgibacillus)的新物种。【结论】湛江硇洲岛潮汐带栉江珧中存在较为丰富的可培养细菌物种多样性和系统发育多样性,并潜藏着较多的新微生物类群(物种)。 相似文献
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Pushkar Shejwalkar 《Inorganica chimica acta》2011,366(1):209-218
New sulfur derivatives of phosphoramidite ligands were synthesized and the impact of the sulfur unit on the spectroscopic properties of their rhodium and iridium complexes was investigated. The new ligands Bn2NPSCH2CH2Sa(P-Sa) (Bn = benzyl, 4), Bn2NPSCHCHSa(CH2)3CaH2(P-Sa)(Ca-Sa) (6) and Bn2NP(4-XC6H4OMe)2 (X = S, 7a; X = O, 7b) were converted to the rhodium and iridium complexes trans-[Rh(CO)Cl(L)2] (L = 4, 6, 7), [RhCl(COD)(L)] (L = 4, 6, 7), [IrCl(COD)(7a)] and [IrCl2Cp∗(6)]. For comparison, some phosphoramidite complexes of these formulations also were synthesized. The new metal complexes were spectroscopically analyzed. For the carbonyl complexes, the νCO IR stretching frequencies were lower than for the corresponding phosphite and phosphoramidite ligands. The 1JPRh coupling constants for the rhodium complexes with the new ligands were also smaller than for the respective phosphoramidite and phosphite complexes. Finally, the 1JPSe coupling constants of the selenides of the new ligands were lower than those of the phosphoramidite ligands but higher than for PPh3. The spectroscopic data reveal that the new thio ligands 4, 6 and 7a are more electron donating than phosphites and phosphoramidites but less electron donating than PPh3. 相似文献
13.
Astrocytes transport the monocarboxylate acetate, but synaptosomes do not. The reason for this is unknown, because both preparations express monocarboxylate transporters (MCT). The transport and metabolism of lactate, another monocarboxylate, was examined in these two preparations, and the results were compared to those for acetate. Lactate transport is more rapid in astrocytes than in synaptosomes, but of lower affinity (Kms of 17 and 4 mM, respectively). Lactate (0.2 mM) is metabolized to CO2 more rapidly in synaptosomes than in astrocytes (rates of 0.37 and 0.07 nmol x mg protein(-1) x min(-1), respectively). The reason for this is unclear, but cellular differences in lactate dehydrogenase isotype expression may be involved. Acetate is metabolized to CO2 more rapidly in astrocytes than in synaptosomes (rates of 0.43 and 0.02 nmol x mg protein(-1) x min(-1), respectively). This is likely due to cellular differences in the expression of monocarboxylate transporter subtypes. 相似文献
14.
Hand JW 《Progress in biophysics and molecular biology》2007,93(1-3):192-194
The first and second sessions of the Workshop focussed on the basics of ultrasound and infrasound, their applications in both industry and medicine, and metrology and protection standards for ultrasound applications. 相似文献
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Gonzalez-Reimers E Rodriguez-Moreno F Martinez-Riera A Mas-Pascual A Delgado-Ureta E Galindo-Martin L Arnay-de la Rosa M Santolaria-Fernandez F 《Biological trace element research》1999,68(1):41-49
To elucidate accumulation of minerals in human iliac arteries with aging, the content of minerals was analyzed by inductively
coupled plasma atomic emission spectrometry. Bilateral common, internal, and external iliac arteries of 16 men and 8 women,
ranging ages from 65 to 93 yr, were examined. It was found that an extremely high accumulation of calcium and phosphorus occurred
in the common iliac artery at old age, being higher than that of the internal and external iliac arteries. It should be noted
that the accumulation of calcium and phosphorus is the highest in the common iliac artery among the human arteries examined
to date.
Regarding sexual differences, the content of calcium and phosphorus in the common and internal iliac arteries was higher in
women than in men, whereas their content in the external iliac artery was lower in women than in men. 相似文献
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18.
J. Morley M.A. Bray R.W. Jones D.H. Nugteren D.A. van Dorp 《Prostaglandins & other lipid mediators》1979,17(5):729-736
The ability of partially purified human and guinea-pig haematogenous cell populations, when cultured in vitro, to metabolise arachidonic acid (AA) has been studied. Supernatants from 24 hour cell culture have been subjected to analysis for products of AA metabolism by gas chromatography with electron-capture detection.The cell types studied were human peripheral blood monocytes (both glass adherent and non-adherent), neutrophils, eosinophils and leukemic leucocytes; thoracic duct lymphocytes and lung alveolar macrophages. From the guinea-pig, induced and non-induced macrophage or neutrophil enriched peritoneal exudate populations, lymph node cells, peritoneal eosinophils and peripheral blood platelets were examined. Supernatants were assayed for the presence of PGE2, PGD2, PGF2α, TXB2 and 6-keto-PGF1α. In all types studied PGE2 and TXB2 were the major products formed. The identification of PGE2 and TXB2 was confirmed by GC/MS with multiple ion monitoring.The results have been compared with other reports and their possible significance discussed in relation to the proposed role of prostaglandins as mediators and modulators in immunopathology. 相似文献
19.
Allergic asthma can be precipitated by many factors. For the atopic person, fungus, pollen, dust mites, cockroach antigens, and diesel exhaust are all agents that may trigger an allergic attack. Cytokines and chemokines are integral mediators of fungal asthma. From the earliest time points, they recruit and activate the cells required for the clearance of fungus as well as being critical factors involved in the immunopathology of this disease. In the final analysis, it is clear that these mediators can act to the benefit or the detriment of the host. 相似文献
20.
Sandra M. Vaz 《Archives of biochemistry and biophysics》2009,484(2):127-431
In spite of the many studies on protein modifications by reactive species, knowledge about the products resulting from the oxidation of protein-aromatic residues, including protein-derived radicals and their stable products, remains limited. Here, we compared the oxidative modifications promoted by peroxynitrite and myeloperoxidase/hydrogen peroxide/nitrite in two model proteins, ribonuclease (6Tyr) and lysozyme (3Tyr/6Trp). The formation of protein-derived radicals and products was higher at pH 5.4 and 7.4 for myeloperoxidase and peroxynitrite, respectively. The main product was 3-nitro-Tyr for both proteins and oxidants. Lysozyme rendered similar yields of nitro-Trp, particularly when oxidized by peroxynitrite. Hydroxylated and dimerized products of Trp and Tyr were also produced, but in lower yields. Localization of the main modified residues indicates that peroxynitrite decomposes to radicals within the proteins behaving less specifically than myeloperoxidase. Nitrogen dioxide is emphasized as an important protein modifier. 相似文献