Tellurite Adsorption onto Bacterial Surfaces
Tellurite Adsorption onto Bacterial Surfaces
复制标题
细菌表面的亚碲酸盐吸附
DOI：
10.1021/acs.est.1c01001
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发表时间：
2021
影响因子：
11.4
通讯作者：
Yee, Nathan
中科院分区：
文献类型：
--
作者：
Goff, Jennifer L.;Wang, Yuwei;Boyanov, Maxim I.;Yu, Qiang;Kemner, Kenneth M.;Fein, Jeremy B.;Yee, Nathan
碲（Te）是一种新兴的污染物，其在环境中的化学转化受到微生物过程的强烈影响。研究了土壤中常见细菌枯草芽孢杆菌对亚碲酸盐[Te（IV），TeO_（32-）]的吸附行为。巯基阻断实验进行了调查的作用，细胞表面巯基网站在碲结合，扩展X射线吸收精细结构（EXAFS）光谱进行，以确定化学形态的吸附碲。结果表明，亚碲酸盐可与细菌胞外聚合物（EPS）中的巯基发生反应。枯草芽孢杆菌在结合到EPS中的巯基位点时，Te从Te-O键变为Te-S配位。对表面结合分子的进一步分析表明，B.枯草杆菌含有蛋白质。去除蛋白质EPS显着降低亚碲酸盐吸附和巯基表面位点浓度。这些研究结果表明，巯基结合在EPS中起着关键作用的亚碲酸盐吸附在细菌表面。
Tellurium (Te) is an emerging contaminant and its chemical transformation in the environment is strongly influenced by microbial processes. In this study, we investigated the adsorption of tellurite [Te(IV), TeO32–] onto the common soil bacteriumBacillus subtilis. Thiol-blocking experiments were carried out to investigate the role of cell surface sulfhydryl sites in tellurite binding, and extended X-ray absorption fine structure (EXAFS) spectroscopy was performed to determine the chemical speciation of the adsorbed tellurite. The results indicate that tellurite reacts with sulfhydryl functional groups in the extracellular polymeric substances (EPS) produced byB. subtilis. Upon binding to sulfhydryl sites in the EPS, the Te changes from Te–O bonds to Te–S coordination. Further analysis of the surface-associated molecules shows that the EPS ofB. subtiliscontain proteins. Removal of the proteinaceous EPS dramatically decreases tellurite adsorption and the sulfhydryl surface site concentration. These findings indicate that sulfhydryl binding in EPS plays a key role in tellurite adsorption on bacterial surfaces.