State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan 430070, PR China.
Colloids Surf B Biointerfaces. 2010 Oct 1;80(1):79-85. doi: 10.1016/j.colsurfb.2010.05.037. Epub 2010 Jun 1.
Equilibrium adsorption along with scanning electron microscopy (SEM), Fourier transform infrared (FTIR) and isothermal titration calorimetry (ITC) techniques were employed to investigate the adhesion of Pseudomonas putida on goethite. The adhesion isotherm revealed the high affinity of P. putida for goethite. The SEM analysis also showed a tight association between bacteria and mineral particles. Larger amounts of adhesion of bacteria on goethite were observed at pH lower than the isoelectric point (IEP) of goethite. The bacterial adhesion increased with increasing concentration of K(+). The calorimetric results demonstrated that the P. putida-goethite adhesion was an exothermic process. The adhesion enthalpy increased with increasing pH and concentrations of electrolyte. The increase of the negative enthalpy with increment of temperature indicated that the bacteria-goethite adhesion was an enthalpy-driven process. Electrostatic interactions and hydrogen bonding were considered to contribute mainly to the adhesion of bacterial adhesion on goethite. The data obtained in this study would provide valuable information for a better understanding of the mechanisms of mineral-microorganism interactions in soil and associated environments.
采用平衡吸附、扫描电子显微镜（SEM）、傅里叶变换红外光谱（FTIR）和等温热滴定技术研究了假单胞菌属在针铁矿上的附着。附着等温线表明，假单胞菌属对针铁矿具有高亲和力。SEM 分析还表明，细菌和矿物颗粒之间存在紧密的联系。在低于针铁矿等电点（IEP）的 pH 值下，观察到细菌在针铁矿上的附着量更大。随着 K(+)浓度的增加，细菌在针铁矿上的附着量增加。量热结果表明，假单胞菌-针铁矿附着是一个放热过程。附着焓随 pH 值和电解质浓度的增加而增加。随着温度的升高，负焓的增加表明细菌-针铁矿附着是一个焓驱动的过程。静电相互作用和氢键被认为是细菌附着在针铁矿上的主要贡献因素。本研究获得的数据将为更好地理解土壤和相关环境中矿物-微生物相互作用的机制提供有价值的信息。
