厌氧条件在不同Fe( II) 浓度测定方法中必要性的比较研究

厌氧是目前Fe(II)测定方法中常选择的处理方式,但是不可避免会给实验操作带来不便。为了方便、准确地测定铁还原体系中的Fe(II)浓度,对比研究了厌氧条件对草酸—草酸铵和盐酸两种典型浸提方法测定Fe(II)浓度的影响。结果表明:对于草酸—草酸铵浸提法,厌氧条件是必须的,以防止提取液中的Fe(II)被氧化,而且样品浸提1 h 便可用于Fe(II)的测定;然而对于盐酸浸提法,厌氧条件却并不是必须的,对Fe(II)浓度测定基本不产生影响。因此,为简化实验操作或在没有厌氧条件的情况,可利用盐酸浸提法测定铁还原体系中Fe(II)浓度

The Role of Microorganisms in the Geochemical Iron Cycle

铁元素虽然只在地壳含量中位列第4,但却是地球上分布最广的变价金属元素之一,微生物介导的铁循环及其与生源要素碳、氮、氧和硫等耦合的氧化还原反应是微生物地球化学循环的重要驱动力.由于铁循环过程中氧化态三价铁Fe(Ⅲ)在环境p H条件下大多以不溶状态存在,因而由其参与的地球化学循环进程通常较为缓慢.研究表明,微生物在铁元素的地球化学循环过程中起着举足轻重的作用,并在该过程中参与矿物的生成与转化.近年来的最新研究发现,参与地球化学铁循环的微生物之间,微生物与矿物之间,以及矿物介导的微生物之间存在着多样的相互作用,而含铁矿物介导的微生物胞外电子传递机制是其中最受瞩目的研究热点.本文综述了微生物介导的地球..

Trisomy 21-induced Dysregulation of Microglial Homeostasis in Alzheimer’s Brains is Mediated by USP25

阿尔茨海默病（Alzheimer’s disease, AD）是一种最为常见的与记忆、认知能力退化相关的渐进性神经退行性疾病。唐氏综合征（Down’s syndrome, DS）是早发型阿尔茨海默病的一个重要风险因素，作为最常见的智力障碍遗传疾病，厦门大学医学院神经科学研究所王鑫教授团队揭示了治疗阿尔茨海默病和唐氏综合征新的治疗靶点，并且在小鼠模型上利用USP25小分子抑制剂成功地改善了阿尔茨海默病小鼠的认知功能，缓解了神经退行性病变的病理进程。该研究工作由王鑫教授指导完成，厦门大学医学院助理教授郑秋阳和博士生李桂林完成主要实验工作，王世华、朱琳、高月、邓青芳、张洪峰、张丽珊、吴美玲、狄安洁参与了部分研究工作。厦门大学医学院许华曦、赵颖俊和孙灏教授在研究过程中给予大力帮助和支持，清华大学董晨教授提供了Usp25基因敲除小鼠，厦门大学附属妇女儿童医院周裕林教授和郑良楷博士帮助收集了脑组织样品。Down syndrome (DS), caused by trisomy of chromosome 21, is the most significant risk factor for early-onset Alzheimer’s disease (AD); however, underlying mechanisms linking DS and AD remain unclear. Here, we show that triplication of homologous chromosome 21 genes aggravates neuroinflammation in combined murine DS-AD models. Overexpression of USP25, a deubiquitinating enzyme encoded by chromosome 21, results in microglial activation and induces synaptic and cognitive deficits, whereas genetic ablation of Usp25 reduces neuroinflammation and rescues synaptic and cognitive function in 5×FAD mice. Mechanistically, USP25 deficiency attenuates microglia-mediated proinflammatory cytokine overproduction and synapse elimination. Inhibition of USP25 reestablishes homeostatic microglial signatures and restores synaptic and cognitive function in 5×FAD mice. In summary, we demonstrate an unprecedented role for trisomy 21 and pathogenic effects associated with microgliosis as a result of the increased USP25 dosage, implicating USP25 as a therapeutic target for neuroinflammation in DS and AD.This work was supported by the National Natural Science Foundation of China (31871077, 81822014, and 81571176 to X.W.; 81701130 to Q.Z.), the National Key R&D Program of China (2016YFC1305900 to X.W.), the Natural Science Foundation of Fujian Province of China (2017J06021 to X.W.), the Fundamental Research Funds for the Chinese Central Universities (20720150061 to X.W.), and the BrightFocus Foundation (A2018214F to Yingjun Zhao). 该研究工作得到国家重点研发计划项目、国家自然科学基金、福建省自然科学基金、厦门大学校长基金的资助和支持

Salt-tolerant methanogenic archaea and application thereof

本发明属于微生物领域，具体涉及一株耐盐的产甲烷古菌及其应用。产甲烷古菌Methanobacterium sp.strain YSL，保藏于中国微生物菌种保藏管理委员会普通微生物中心，保藏号为CGMCC NO.18876。该菌株是目前报道的首例能利用甲酸但不能利用氢气的产甲烷古菌，可以提高沼气池中的产甲烷效率，在生物能源方面具有广阔的应用前景

海岸带典型生境甲烷杆菌种间直接电子传递机制的研究

Methanogens produce methane via direct interspecies electron transfer (DIET), which is an important way for the recent discovery of methane emissions in anoxic habitats. Methanobacterium is an important group of methanogens in coastal habitats, but there is no evidence of its participation in DIET for a long time. In this review, the importance of DIET participated by methanogens to the carbon cycle in typical coastal habitats was summarized, and the environmental conditions in typical coastal habitats that favor Methanobacterium participating in DIET for methanogenesis were emphatically analyzed. The theoretical supports provided by domestic and international researches on the microbiological mechanisms of methanogenesis for Methanobacterium participating in DIET mechanism were also discussed. Future studies on the DIET mechanism of Methanobacterium in typical coastal habitats will provide theoretical supports for accurate assessment of methane emissions in coastal ecosystems

Desulfurization Vibrio and application thereof

本发明属于微生物领域，具体涉及一株具有电活性的脱硫弧菌及其应用。脱硫弧菌Desulfovibrio sp.strain JY，保藏于中国微生物菌种保藏管理委员会普通微生物中心，保藏日期为2019年10月28日，保藏号为CGMCC NO.18877。该菌能利用乙醇或乳酸还原硫酸盐产生乙酸代谢产物。该菌株在淡水和海水环境中均具有很强的产电能力，最大电流输出密度可达243.2mA/m2。该菌株是目前报道的首例电活性脱硫弧菌，可为探索微生物胞外电子传递在腐蚀中的作用提供模式菌株，进而为海洋金属腐蚀防控技术提供策略

The present invention relates to a method for quickly screening plastics-degrading microorganism based on polymer membrane electrode sensing technology

本发明公开了一种快速筛选具有塑料降解活性微生物的方法。更详细地公开了一种基于聚合物膜电极传感技术快速筛选塑料降解微生物的方法。利用微生物对磁性复合材料外层包裹的塑料层的降解能力，调控复合材料中指示离子释放通量，再通过聚合物膜离子选择性电极对复合材料的响应信号、指示离子通量与微生物降解塑料之间关系，实现对降解塑料微生物的定性和/或定量检测降解效率；所述复合材料为经塑料包覆的磁性颗粒所形成。与传统筛选具有塑料降解活性微生物的方法相比，本发明在数小时内即可实现。本发明为塑料降解微生物的快速筛选提供了新思路

黄素介导的滨海湿地电活性微生物与 产甲烷菌间电子传递机制

Microbial interspecies electron transfer (IET) is the driving force of elements cycling and energy metabolism in epigeo sphere, especially in the coastal wetlands, where are the most intense interaction between sea and land and have extremely rich electron donors and acceptors. Our previous studies have demonstrated that both activated carbon and magnetite can facilitate IET between elec trogenic Geobacters or Geobacter and methanogens in coastal wetlands. Flavins are important electron carriers of anaerobic microorganisms, and studies have shown that they can promote microbial extracellular electron transfer. However, whether flavins could promote IET between the electrogenic bacteria and the bacteria or the archaea in coastal wetlands are still unknown. In this review, interspecies electron transfer of syntrophic methanogenesis between electricigens and methanogens, and the practical significance of the study on mechanisms of flavins-mediated electron transfer between electricigens and methanogens in coastal wetlands were briefly summarized. Future studies on microbial mechanisms of flavins-mediated electron transfer between electricigens and methanogens will provide theo retical basis for more scientific assessment methane emission of coastal wetlands and the construction of ecological model.</p

微生物在地球化学铁循环过程中的作用

铁元素虽然只在地壳含量中位列第4,但却是地球上分布最广的变价金属元素之一,微生物介导的铁循环及其与生源要素碳、氮、氧和硫等耦合的氧化还原反应是微生物地球化学循环的重要驱动力.由于铁循环过程中氧化态三价铁Fe(Ⅲ)在环境p H条件下大多以不溶状态存在,因而由其参与的地球化学循环进程通常较为缓慢.研究表明,微生物在铁元素的地球化学循环过程中起着举足轻重的作用,并在该过程中参与矿物的生成与转化.近年来的最新研究发现,参与地球化学铁循环的微生物之间,微生物与矿物之间,以及矿物介导的微生物之间存在着多样的相互作用,而含铁矿物介导的微生物胞外电子传递机制是其中最受瞩目的研究热点.本文综述了微生物介导的地球..

硅光电负阻器件的光双稳态瞬态特性

在该文中，一方面对电路参数与硅光电负阻器件的光学双稳态开关时间的关系进行了研究，另一方面对器件在低、中、高三个不同输入光强区的光学双稳态响应的变化趋势进行了研究。硅光电负阻器件包括有各种类型，该文主要对“λ”型双极光电负阻晶体管(PLBT)以电阻和光电二极管作为负载的情况进行了讨论