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| DOI | 10.1111/gbi.12332 |
| The kinetics of siderophore-mediated olivine dissolution | |
| Torres M.A.; Dong S.; Nealson K.H.; West A.J. | |
| 发表日期 | 2019 |
| ISSN | 14724677 |
| 起始页码 | 401 |
| 结束页码 | 416 |
| 卷号 | 17期号:4 |
| 英文摘要 | Silicate minerals represent an important reservoir of nutrients at Earth's surface and a source of alkalinity that modulates long-term geochemical cycles. Due to the slow kinetics of primary silicate mineral dissolution and the potential for nutrient immobilization by secondary mineral precipitation, the bioavailability of many silicate-bound nutrients may be limited by the ability of micro-organisms to actively scavenge these nutrients via redox alteration and/or organic ligand production. In this study, we use targeted laboratory experiments with olivine and the siderophore deferoxamine B to explore how microbial ligands affect nutrient (Fe) release and the overall rate of mineral dissolution. Our results show that olivine dissolution rates are accelerated in the presence of micromolar concentrations of deferoxamine B. Based on the non-linear decrease in rates with time and formation of a Fe3+-ligand complex, we attribute this acceleration in dissolution rates to the removal of an oxidized surface coating that forms during the dissolution of olivine at circum-neutral pH in the presence of O2 and the absence of organic ligands. While increases in dissolution rates are observed with micromolar concentrations of siderophores, it remains unclear whether such conditions could be realized in natural environments due to the strong physiological control on microbial siderophore production. So, to contextualize our experimental results, we also developed a feedback model, which considers how microbial physiology and ligand-promoted mineral dissolution kinetics interact to control the extent of biotic enhancement of dissolution rates expected for different environments. The model predicts that physiological feedbacks severely limit the extent to which dissolution rates may be enhanced by microbial activity, though the rate of physical transport modulates this limitation. © 2019 John Wiley & Sons Ltd |
| 关键词 | alkalinitybioavailabilitydissolutionimmobilizationligandmicrobial activityolivinereaction kineticssecondary mineralsiderophoresilicate mineraliron derivativemagnesium derivativeolivinesiderophoresilicatebiological modelchemistrykineticsmicrofloraphysiologysolubilityIron CompoundsKineticsMagnesium CompoundsMicrobiotaModels, BiologicalSiderophoresSilicatesSolubility |
| 语种 | 英语 |
| 来源机构 | Geobiology |
| 文献类型 | 期刊论文 |
| 条目标识符 | http://gcip.llas.ac.cn/handle/2XKMVOVA/133228 |
| 推荐引用方式 GB/T 7714 | Torres M.A.,Dong S.,Nealson K.H.,et al. The kinetics of siderophore-mediated olivine dissolution[J]. Geobiology,2019,17(4). |
| APA | Torres M.A.,Dong S.,Nealson K.H.,&West A.J..(2019).The kinetics of siderophore-mediated olivine dissolution.,17(4). |
| MLA | Torres M.A.,et al."The kinetics of siderophore-mediated olivine dissolution".17.4(2019). |
| 条目包含的文件 | 条目无相关文件。 | |||||
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