氧化亚铁硫杆菌的胞外电子传递研究

使用循环伏安、计时电流等电化学方法研究了氧化亚铁硫杆菌(Acidithiobacillus ferrooxidans,At.f)的胞外电子传递机理.通过比较分别以亚铁离子和单质硫为电子供体培养的At.f的循环伏安曲线的还原峰可知,At.f具有胞外电子传递能力;恒压-0.4 V时,加入亚铁离子能够促进At.f的胞外电子传递;好氧条件比厌氧条件产生/变化的电流大1个数量级,说明At.f在好氧条件下具有较强的电化学活性.此外,采用X射线衍射、傅里叶变换红外光谱及扫描电子显微镜等对菌体的表面特征进行了分析.

Research on Extracellular Electron Transfer of Acidithiobacillus Ferrooxidans

Extracellular electron transfer of Acidithiobacillus ferrooxidans(At. f) was investigated using cyclic voltammetry and chronoamperometry. Compared with cyclic voltammograms with ferrous ion or sulfur as electron donors, At. f has the extracellular electron transfer capability, and the reduction peak is produced by At. f under the condition of a constant potential -0.4 V, adding ferrous ion to the system could improve extracellular electron transfer. The current produced/changed under aerobic condition is more than one order of magnitude than under anaerobic condition. It illustrates that At. f has the stronger electrochemical activity under aerobic condition. In addition, surface characteristics of At. f were analyzed using X-ray diffraction, Fourier transform infrared spectra and scanning electron microscopy. These results could provide a basis for improving metal leaching rate.