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厌氧氨氧化是环境领域和微生物领域的一个重大发现,对于认识氮素生物地球化学循环、丰富微生物学理论和开发新型生物脱氮工艺均具有巨大的推动作用.近年来对厌氧氨氧化菌的研究取得了许多突破性成果,探明了个体形态特征、细胞化学组分特征、富集培养与分离特征、生理生化特征以及生态学特征,提出了厌氧氨氧化代谢模型,纯化研究了多种厌氧氨氧化酶,分离获得和分类鉴定了5属9种厌氧氨氧化菌,建立了厌氧氨氧化菌科(Anammoxaceae).本文系统介绍了厌氧氨氧化菌的特性,详细描述了9种已被鉴定的厌氧氨氧化菌. 相似文献
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《浙江大学学报(农业与生命科学版)》2019,(2)
厌氧氨氧化(anaerobic ammonium oxidation, ANAMMOX)通常指微生物在厌氧条件下,以亚硝酸根为电子受体,将铵根离子氧化成氮气的过程,主要由浮霉菌门(Planctomycetales)细菌驱动。厌氧氨氧化菌广泛分布于陆地与海洋生态系统里,在全球氮循环中发挥着重要的作用。本文综合分析了在群落水平、细胞水平、分子和组学水平下厌氧氨氧化过程的生态学研究进展,结合不同尺度下的方法与技术介绍,初步探讨和展望了不同生态系统中厌氧氨氧化的前沿问题与研究方向。 相似文献
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添加铬、铁及葡萄糖对土壤中异化铁还原的影响 总被引：1，自引：3，他引：1
采用水稻土为供试土壤,通过添加氧化铁、铬酸盐和葡萄糖的模拟试验,在厌氧培养条件下测定了土壤中可浸提态的亚铁和铬( )浓度的变化,探讨了有机碳源及Cr( )、Fe对厌氧条件下水稻土中微生物铁还原的影响及Fe( )和Cr( )还原的竞争关系。结果表明,添加碳源和氧化铁后,能有效促进厌氧条件下水稻土中铁的异化还原过程,显著减小土壤中铬( )浓度;添加Cr( ),将导致土壤中铁还原滞后;厌氧水稻土中Fe( )和Cr( )的竞争还原机制为,有机电子供体导致氧化铁发生微生物还原,产生的Fe( )引起土壤中Cr( )的化学还原。 相似文献
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[目的]培养高活性的亚硝化生物膜,再将其作为接种微生物启动ANAMMOX反应器。[方法]试验通过监测进出水中NH4^＋-N和NO2--N的变化情况判定反应器工作环境是否由亚硝化为主逐步转变为以厌氧氨氧化为主,继而判定厌氧氨氧化反应器的启动是否完成。[结果]反应器在第185～201天运行稳定,亚硝氮与氨氯的平均去除比例分别为0．65和0．62,而厌氧状态下氨氮和亚硝氮以一定的比例被同时去除是厌氧氨氧化反应器成功运行的特征之一。[结论]亚硝化微生物作为ANAMMOX反应器的接种微生物是可行的。 相似文献
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采用一套有效容积为5L的ASBR厌氧氨氧化反应器,接种普通城市污水处理厂污泥浓缩池污泥,对厌氧氨氧化反应过程的启动进行研究.运行表明:可将反应器启动阶段分为污泥初期适应阶段、污泥表现厌氧氨氧化活性阶段、污泥厌氧氨氧化活性增强阶段及污泥厌氧氨氧化活性稳定阶段等4个阶段共117 d.反应器稳定后,NH4+-N、NO2--N、TN的去除率分别达到100％、100％、88％,并获得红褐色的厌氧氨氧化活性污泥.反应后113 d对污泥进行扫描电镜观察,结果初步证明培养出了厌氧氨氧化菌. 相似文献
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Observations of the infrared absorption bands attributed to the stretching vibrations of hydroxyl groups in biotite containing predominantly ferrous iron show that the dipole moments of the hydroxyls associated with ferrous iron are oriented perpendicular to the cleavage plane of the lattice. Oxidation in the biotite from ferrous iron to ferric iron results in the disappearance of the infrared absorption bands due to the hydroxyls associated with ferrous iron. The dipole moments of the hydroxyls associated with ferric iron in the oxidized biotite have been shown to be in an inclined position with respect to the cleavage plae. Our experiments confirm the hypothesis of Barshad and Kishk regarding the effect of oxidation on the replaceability of interlayer potassium ions in biotite by ammonium ions. 相似文献
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Electron exchange involving the valence states of iron occurs via water bridges. Molecular oxygen reversibly displaces the sole coordinated water of the ferrous iron in hemoglobin, and, in the absence of this ready path for electron transfer, the oxygen is transported without oxidation of the ferrous iron of hemoglobin. 相似文献
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In a small mountain stream in Colorado that receives acidic mine drainage, photoreduction of ferric iron results in a well-defined increase in dissolved ferrous iron during the day. To quantify this process, an instream injection of a conservative tracer was used to measure discharge at the time that each sample was collected. Daytime production of ferrous iron by photoreduction was almost four times as great as nighttime oxidation of ferrous iron. The photoreduction process probably involves dissolved or colloidal ferric iron species and limited interaction with organic species because concentrations of organic carbon are low in this stream. 相似文献
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Acidic mine drainage: the rate-determining step 总被引：1，自引：0，他引：1
The rate-determining step in the oxidation of iron pyrite and the formation of acidity in streams associated with coal and copper mines is the oxidation of ferrous iron. Effective pollution abatement necessitates control ling this reaction. 相似文献
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多糖对水稻土中异化Fe(Ⅲ)还原过程的影响 总被引：2，自引：0，他引：2
本研究通过土壤泥浆厌氧培养的方法,在水稻土中添加不同质量浓度淀粉和纤维素,探讨多糖作为电子供体对异化Fe(Ⅲ)还原过程的影响。结果表明,在2种水稻土泥浆的厌氧培养过程中,淀粉、纤维素可以促进水稻土中的异化Fe(Ⅲ)还原,其质量浓度在0～20 g/L时,Fe(Ⅱ)最大累积量和速率常数随质量浓度增加而增大,其对土壤中Fe(Ⅲ)氧化物异化还原的促进作用与土壤pH、有机质和无定形铁含量有关。对培养过程中pH与异化铁还原动力学数据的比较发现,在微生物正常生长的pH范围内,较低的pH利于Fe(Ⅲ)的还原。 相似文献
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对好氧剩余污泥重金属生物沥滤过程中可能存在的抑制作用进行了系统研究.结果表明,丽华污泥(取自常州丽华污水处理厂)和城东污泥(苏州城东污水处理厂)及其上清液对氧化亚铁硫杆菌(Acidithiobacillus ferrooxidans)的生长及Fe2 氧化作用均具有强烈抑制作用,而乙酸和丙酸是引起上述抑制作用的主要因子.采用不同固体含量污泥悬液进行模拟培养试验,结果证明污泥中的乙酸和丙酸主要来源于浓缩池内污泥有机质的厌氧分解.在污泥生物沥滤过程中,乙酸和丙酸的存在对Zn的溶出效率没有不利影响,但污泥的酸化速率显著下降,丽华污泥和城东污泥中Cu的沥滤时间分别比对照延长6 d和2 d,严重影响生物沥滤工艺的总体效率. 相似文献
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本文通过田间对比和水培模拟不同亚铁浓度里加钾素肥的试验,结果表明:在还原条件下增施钾肥后,能明显地降低水稻体内亚铁和活性铁的含量,白根数目增多、根系氧化力提高、叶片光合强度增强、稻体内蛋白氮增加,非蛋白氮减少,促进了稻体内代谢的平衡,有效地防了亚铁的中毒。 相似文献
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[目的]建立调控肉制品脂质氧化程度的新方法。[方法]以TBA、POV和pH为评判指标,借助铁盐协同超高压调控肉制品中脂质氧化程度,并优化工艺参数。[结果]试验得出,评判指标TBA为2．78meq／kg,POV为35．80meq／kg,pH变化不显著;优化的工艺条件为：压力200MPa,保压时间12rain,亚铁离子浓度0．085mg／g。[结论]添加铁盐并经超高压处理,可促进肉制品脂质适度氧化,增加羰基化合物的生成。 相似文献
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Hydroxylation of proline and the intracellular accumulation of a polypeptide precursor of collagen 总被引：12，自引：0，他引：12
Autoradiographs of embryonic cartilage indicated that labeled protein accumnulated intracellularly when the tissue was incubated with tritiated proline, and when the hydroxylation of proline was inhibited by anaerobic conditions or by a chelator for ferrous iron. The labeled protein apparently corresponds to protocollagen. the polypeptide precursor of collagen which serves as a substrate for the enzymatic synthesis of hydroxyproline. 相似文献
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Previous studies of anaerobic biocorrosion have suggested that microbial sulfur and phosphorus products as well as cathodic hydrogen consumption may accelerate anaerobic metal oxidation. Methanogenic bacteria, which normally use molecular hydrogen (H(2)) and carbon dioxide (CO(2)) to produce methane (CH(4)) and which are major inhabitants of most anaerobic ecosystems, use either pure elemental iron (Fe(0)) or iron in mild steel as a source of electrons in the reduction of CO(2) to CH(4). These bacteria use Fe(0) oxidation for energy generation and growth. The mechanism of Fe(0) oxidation is cathodic depolarization, in which electrons from Fe(0) and H(+) from water produce H(2), which is then released for use by the methanogens; thermodynamic calculations show that significant Fe(0) oxidation will not occur in the absence of H(2) consumption by the methanogens. The data suggest that methanogens can be significant contributors to the corrosion of iron-containing materials in anaerobic environments. 相似文献