A Novel Aerobic Mechanism for Reductive Palladium Biomineralization and Recovery by Escherichia coli
A Novel Aerobic Mechanism for Reductive Palladium Biomineralization and Recovery by Escherichia coli
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DOI：
10.1080/01490451.2015.1069911
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发表时间：
2016-03-15
影响因子：
2.3
通讯作者：
Lloyd, Jonathan R.
中科院分区：
文献类型：
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作者：
Foulkes, Joanne M.;Deplanche, Kevin;Lloyd, Jonathan R.
有氧培养的大肠杆菌细胞通过一种以甲酸盐为电子供体的新机制还原Pd(II)。利用扩展的X射线吸收精细结构实时监测了这种还原。透射电子显微镜分析表明，经X-射线衍射证实，Pd(0)纳米粒子在细胞外析出。测定了缺乏一系列氧化还原酶的大肠杆菌突变株对Pd(II)的还原速率，表明这是一种钼蛋白介导的机制，不同于先前描述的用于厌氧培养的大肠杆菌的氢酶介导的Pd(II)还原。讨论了Pd(II)回收和生物Pd催化剂制备的潜在意义。
Aerobically grown E. coli cells reduced Pd(II) via a novel mechanism using formate as the electron donor. This reduction was monitored in real-time using extended X-ray absorption fine structure. Transmission electron microscopy analysis showed that Pd(0) nanoparticles, confirmed by X-ray diffraction, were precipitated outside the cells. The rate of Pd(II) reduction by E. coli mutants deficient in a range of oxidoreductases was measured, suggesting a molybdoprotein-mediated mechanism, distinct from the hydrogenase-mediated Pd(II) reduction previously described for anaerobically grown E. coli cultures. The potential implications for Pd(II) recovery and bioPd catalyst fabrication are discussed.