Fate of Cd during microbial Fe(III) mineral reduction by a novel and Cd-tolerant Geobacter species.
Fate of Cd during microbial Fe(III) mineral reduction by a novel and Cd-tolerant Geobacter species.
复制标题
DOI：
10.1021/es403365w
复制
发表时间：
2013-12
影响因子：
11.4
通讯作者：
E. Muehe;M. Obst;A. Hitchcock;T. Tyliszczak;S. Behrens;C. Schröder;James M. Byrne;F. Marc Michel-F.-Marc-M
中科院分区：
文献类型：
--
作者：
E. Muehe;M. Obst;A. Hitchcock;T. Tyliszczak;S. Behrens;C. Schröder;James M. Byrne;F. Marc Michel-F.-Marc-M
Fe（III）（oxyhydr）氧化物通过提供吸附的反应表面而影响环境中污染物的流动性。这包括有毒金属镉（Cd），它普遍存在于农业土壤中，并被作物吸收。Fe（III）还原菌可以通过Fe（III）矿物溶解来动员这些污染物，或者通过吸附到次生Fe矿物或与次生Fe矿物共沉淀来使其溶解。到目前为止，没有太多的是已知的Fe（III）矿物相关的镉在微生物Fe（III）还原的命运。在这里，我们描述了一个新的Geophyssp.菌株Cd 1的分离从镉污染的现场，其中该菌株占10（4）细胞g（-1）干土壤。菌株镉1减少了不良结晶铁（III）羟基氧化铁在至少高达112毫克镉L（-1）的存在下。在初始微生物还原镉负载的水铁矿，吸附镉被动员。然而，在连续的微生物Fe（III）还原，镉被固定的吸附和/或共沉淀内新形成的次生矿物，含有钙，铁和碳酸盐，这意味着形成的奥陶石-菱铁矿-方解石（CdCO 3-FeCO 3-CaCO 3）混合矿物相。我们的数据表明，微生物介导的铁矿物的营业额影响镉在土壤中的流动性，可能会改变镉吸收到食品或植物修复植物的动态。
Fe(III) (oxyhydr)oxides affect the mobility of contaminants in the environment by providing reactive surfaces for sorption. This includes the toxic metal cadmium (Cd), which prevails in agricultural soils and is taken up by crops. Fe(III)-reducing bacteria can mobilize such contaminants by Fe(III) mineral dissolution or immobilize them by sorption to or coprecipitation with secondary Fe minerals. To date, not much is known about the fate of Fe(III) mineral-associated Cd during microbial Fe(III) reduction. Here, we describe the isolation of a new Geobacter sp. strain Cd1 from a Cd-contaminated field site, where the strain accounts for 10(4) cells g(-1) dry soil. Strain Cd1 reduces the poorly crystalline Fe(III) oxyhydroxide ferrihydrite in the presence of at least up to 112 mg Cd L(-1). During initial microbial reduction of Cd-loaded ferrihydrite, sorbed Cd was mobilized. However, during continuous microbial Fe(III) reduction, Cd was immobilized by sorption to and/or coprecipitation within newly formed secondary minerals that contained Ca, Fe, and carbonate, implying the formation of an otavite-siderite-calcite (CdCO3-FeCO3-CaCO3) mixed mineral phase. Our data shows that microbially mediated turnover of Fe minerals affects the mobility of Cd in soils, potentially altering the dynamics of Cd uptake into food or phyto-remediating plants.