Real-Time Manganese Phase Dynamics during Biological and Abiotic Manganese Oxide Reduction.
Real-Time Manganese Phase Dynamics during Biological and Abiotic Manganese Oxide Reduction.
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DOI：
10.1021/acs.est.5b04834
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发表时间：
2016-04-19
影响因子：
11.4
通讯作者：
Fischer WW
中科院分区：
文献类型：
--
作者：
Johnson JE;Savalia P;Davis R;Kocar BD;Webb SM;Nealson KH;Fischer WW
锰氧化物通常具有很高的活性，很容易被各种无机化学物质还原，在微生物厌氧呼吸过程中也很容易被生物还原。为了评估这些不同还原途径的反应机理及其潜在的持久产物，我们测量了化学物种(硫化物和亚铁)介导的微生物氧化锰(IV)还原和常见金属还原微生物坚尼希瓦氏菌MR-1在几种端元条件下的序列级数，使用同步加速器X射线光谱测量，辅之以整个反应过程中收集的沉淀物的X射线衍射和拉曼光谱。在这些实验中产生的结晶相或潜在的长寿命相包括锰(II)-磷酸盐、锰(II)-碳酸盐和锰(III)-氢氧化物。对这些离散相形成的主要控制因素是碱度、生产和溶液条件，如无机碳和磷酸盐的有效性。长寿命氧化锰(III)的形成似乎取决于水中Mn2+的生成以及体系中电子给体和电子受体的相对比例。这些实时测量识别了锰(IV)氧化物还原过程中的矿物学产物，有助于了解各种锰(IV)氧化物还原途径的机理，并有助于解释在富锰环境中活跃发生的过程，并记录在富锰地层的地质记录中。
Manganese oxides are often highly reactive and easily reduced, both abiotically, by a variety of inorganic chemical species, and biologically during anaerobic respiration by microbes. To evaluate the reaction mechanisms of these different reduction routes and their potential lasting products, we measured the sequence progression of microbial manganese(IV) oxide reduction mediated by chemical species (sulfide and ferrous iron) and the common metal-reducing microbe Shewanella oneidensis MR-1 under several endmember conditions, using synchrotron X-ray spectroscopic measurements complemented by X-ray diffraction and Raman spectroscopy on precipitates collected throughout the reaction. Crystalline or potentially long-lived phases produced in these experiments included manganese(II)-phosphate, manganese(II)-carbonate, and manganese(III)-oxyhydroxides. Major controls on the formation of these discrete phases were alkalinity production and solution conditions such as inorganic carbon and phosphate availability. The formation of a long-lived Mn(III) oxide appears to depend on aqueous Mn2+ production and the relative proportion of electron donors and electron acceptors in the system. These real-time measurements identify mineralogical products during Mn(IV) oxide reduction, contribute to understanding the mechanism of various Mn(IV) oxide reduction pathways, and assist in interpreting the processes occurring actively in manganese-rich environments and recorded in the geologic record of manganese-rich strata.
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影响因子：
5
作者：
Bargar, JR;Tebo, BM;Villinski, JE
通讯作者：
Villinski, JE
影响因子：
11.4
作者：
Elzinga, Evert J.
通讯作者：
Elzinga, Evert J.
影响因子：
5
作者：
Dick, Gregory J.;Clement, Brian G.;Tebo, Bradley M.
通讯作者：
Tebo, Bradley M.
DOI：
10.1073/pnas.0907468107
发表时间：
2010-01-05
影响因子：
11.1
作者：
Harris, H. W.;El-Naggar, M. Y.;Nealson, K. H.
通讯作者：
Nealson, K. H.
影响因子：
3.1
作者：
Bargar, JR;Tebo, BM;Villalobos, M
通讯作者：
Villalobos, M