Cadmium adsorption to clay-microbe aggregates: Implications for marine heavy metals cycling
Cadmium adsorption to clay-microbe aggregates: Implications for marine heavy metals cycling
复制标题
粘土微生物聚集体对镉的吸附：对海洋重金属循环的影响
DOI：
10.1016/j.gca.2020.09.002
复制
发表时间：
2020-12
影响因子：
5
通讯作者：
Konhauser Kurt O.
中科院分区：
文献类型：
--
作者：
Zhou Qixing;Liu Yuxia;Li Tian;Zhao Huazhang;Alessi Daniel S.;Liu Weitao;Konhauser Kurt O.
微生物和粘土矿物之间的相互作用影响金属污染物在海洋和陆地环境中的运输和循环。本研究的目的是量化海洋蓝藻聚球藻在类似海水的条件下对溶解镉 (Cd(II)) 的吸附。 PCC 7002，三种常见的粘土矿物（高岭石、蒙脱石和伊利石），以及细胞粘土骨料。我们在此表明，仅聚球藻的实验在 pH 5.5 以上去除了最多的 Cd，其次是 50% 细胞的聚集体，按降序排列：50% 单个粘土、细胞和所有 3 种粘土的聚集体以及单个粘土。电子显微镜成像显示，粘土以切向边缘方向与聚球藻-粘土矿物聚集体中的细胞相关联。使用非静电表面络合建模方法来拟合聚球藻细胞和单个粘土矿物上的 Cd 吸附。然后将所得的 Cd 结合常数与表面官能团 pKa 值和位点浓度结合使用，以使用组分加和性 (CA) 方法准确预测 Cd 吸附到聚球藻-粘土矿物聚集体上的程度。我们观察到，向粘土矿物悬浮液中添加蓝藻细胞会导致粘土矿物的平均聚集体尺寸显着增大，从而提高粘土沉降速率。尽管我们特别关注镉，但我们的研究表明，浮游细菌与粘土矿物的比例是了解金属从水体转移到海底的速率的重要决定因素。
Interactions between microorganisms and clay minerals influence the transport and cycling of metal contaminants in both marine and terrestrial environments. The present study was conducted to quantify the adsorption of dissolved cadmium, Cd(II), under seawater-like conditions to the marine cyanobacteriumSynechococcussp. PCC 7002, three common clay minerals (kaolinite, montmorillonite and illite), as well as cell-clay aggregates. We show here that theSynechococcus-only experiments removed the most Cd above pH 5.5, followed in decreasing order by aggregates of 50% cells:50% individual clays, aggregates of cells and all 3 clays, and individual clays. Electron microscope imaging showed that clays associated in a tangential edge-on orientation to the cells inSynechococcus-clay mineral aggregates. A non-electrostatic surface complexation modeling approach was used to fit Cd adsorption ontoSynechococcuscells and individual clay minerals. The resulting Cd binding constants were then used in consort with surface functional group pKa values and site concentrations to accurately predict the extent of Cd adsorption onto theSynechococcus-clay mineral aggregates using the component additivity (CA) approach. We observed that the addition of cyanobacterial cells to clay mineral suspensions led to significantly larger mean aggregate sizes of clay minerals, enhancing the clay sedimentation rate. Although specifically focused on Cd, our study indicates that the ratio of bacterial plankton to clay minerals is an important determinant in terms of understanding the rate with which metals are transferred from the water column to the seafloor.
登录
查看更多内容
影响因子：
--
作者：
Jianhua Du;R. Pushkarova;R. Smart
通讯作者：
Jianhua Du;R. Pushkarova;R. Smart
影响因子：
3.9
作者：
Yuxia Liu;D. Alessi;S. Flynn;Md Samrat Alam;Weiduo Hao;M. Gingras;Huazhang Zhao;K. Konhauser
通讯作者：
Yuxia Liu;D. Alessi;S. Flynn;Md Samrat Alam;Weiduo Hao;M. Gingras;Huazhang Zhao;K. Konhauser
影响因子：
5
作者：
M. Ueshima;Brian R. Ginn;E. Haack;J. Szymanowski;J. Fein
通讯作者：
M. Ueshima;Brian R. Ginn;E. Haack;J. Szymanowski;J. Fein
DOI：
10.1073/pnas.201150998
发表时间：
2001-09
影响因子：
11.1
作者：
A. Templeton;T. Trainor;S. Traína;A. Spormann;G. Brown
通讯作者：
A. Templeton;T. Trainor;S. Traína;A. Spormann;G. Brown
影响因子：
11.4
作者：
Davis, JA;Coston, JA;Fuller, CC
通讯作者：
Fuller, CC