Microbial degradation of isosaccharinic acid at high pH.
Microbial degradation of isosaccharinic acid at high pH.
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DOI：
10.1038/ismej.2014.125
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发表时间：
2015-02
期刊：
影响因子：
--
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中科院分区：
文献类型：
--
作者：
中水平放射性废物（ILW），占主导地位的放射性废物库存在联合王国的体积基础上，建议通过多屏障深层地质处置设施（GDF）进行处置。ILW是一种非均质的废物形式，其含有大量的包裹在混凝土中的纤维素材料。在设施用地下水重新饱和时，碱性条件将占主导地位，并将导致纤维素的化学降解，产生大量的有机共污染物，特别是异芥子酸（伊萨）。伊萨可以与放射性核素形成可溶性复合物，从而调动它们并对周围环境或“远场”构成潜在威胁。嗜碱微生物采样从遗留石灰工作现场，这是一个类似的ILW-GDF，能够降解伊萨和耦合这种降解的电子受体的减少，将占主导地位的GDF的进展，从一个有氧的“开放阶段”通过硝酸盐和Fe（III）-还原条件后关闭。此外，焦磷酸测序分析表明，细菌的多样性下降的电子受体的还原电位下降，更专业的生物体在厌氧条件下占主导地位。这些结果意味着，伊萨和可比的有机络合剂，最初存在或形成在原位的微生物衰减，可能会发挥作用，在减少流动性的放射性核素从ILW-GDF，促进减少过度悲观的长期性能评估等设施。
Intermediate-level radioactive waste (ILW), which dominates the radioactive waste inventory in the United Kingdom on a volumetric basis, is proposed to be disposed of via a multibarrier deep geological disposal facility (GDF). ILW is a heterogeneous wasteform that contains substantial amounts of cellulosic material encased in concrete. Upon resaturation of the facility with groundwater, alkali conditions will dominate and will lead to the chemical degradation of cellulose, producing a substantial amount of organic co-contaminants, particularly isosaccharinic acid (ISA). ISA can form soluble complexes with radionuclides, thereby mobilising them and posing a potential threat to the surrounding environment or ‘far field'. Alkaliphilic microorganisms sampled from a legacy lime working site, which is an analogue for an ILW-GDF, were able to degrade ISA and couple this degradation to the reduction of electron acceptors that will dominate as the GDF progresses from an aerobic ‘open phase' through nitrate- and Fe(III)-reducing conditions post closure. Furthermore, pyrosequencing analyses showed that bacterial diversity declined as the reduction potential of the electron acceptor decreased and that more specialised organisms dominated under anaerobic conditions. These results imply that the microbial attenuation of ISA and comparable organic complexants, initially present or formed in situ, may play a role in reducing the mobility of radionuclides from an ILW-GDF, facilitating the reduction of undue pessimism in the long-term performance assessment of such facilities.
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影响因子：
3.2
作者：
Kühner, S;Wöhlbrand, L;Rabus, R
通讯作者：
Rabus, R
DOI：
10.1099/ijs.0.63059-0
发表时间：
2004-11-01
影响因子：
2.8
作者：
Santini, JM;Streimann, ICA;Hoven, RNV
通讯作者：
Hoven, RNV
影响因子：
10.7
作者：
Price MN;Dehal PS;Arkin AP
通讯作者：
Arkin AP
影响因子：
2.3
作者：
Burke, Ian T.;Mortimer, Robert J. G.;Stewart, Douglas I.
通讯作者：
Stewart, Douglas I.
影响因子：
2.8
作者：
Mechichi, T;Stackebrandt, E;Fuchs, G
通讯作者：
Fuchs, G