[利用扩展X射线吸收精细结构研究锌（II）与酿酒酵母之间的相互作用机制]

[Interaction mechanism between Zn(II) and Saccharomyces cerevisiae using EXAFS].

作者信息

Chen Can, Xie Ya-ning, Du Yong-hua, Wang Jian-long

机构信息

Laboratory of Environmental Technology, Institute of Nuclear and New Energy Technology, Tsinghua University, Beijing 100084, China.

出版信息

Huan Jing Ke Xue. 2008 Jun;29(6):1666-70.

PMID:18763520

Abstract

The extended X-ray absorption fine structure spectroscopy (EXAFS) was used to investigate the mechanisms of interaction between Zn(II) and Saccharomyces cerevisiae. The nature of the zinc center in the yeast cells exposed to different Zn(II) concentrations and initial pH was determined by Zn K-edge X-ray absorption spectroscopy. The experimental results suggested that the adsorbed zinc ion on the yeast was the mixture of tetrahedron and octahedron structure, and Zn-O bond length changed within 0.197-0.203 nm and coordination number varied between 4.3 and 3.2 under different conditions. Increase of the initial concentration of Zn(II) and initial pH value decreased the coordination number of Zn-O. Zn-O bond length and coordination number of the live cells of the yeast was lower than that of dead cells.

摘要

扩展X射线吸收精细结构光谱（EXAFS）被用于研究锌离子（Zn(II)）与酿酒酵母之间的相互作用机制。通过锌K边X射线吸收光谱确定了暴露于不同Zn(II)浓度和初始pH值下酵母细胞中锌中心的性质。实验结果表明，酵母表面吸附的锌离子是四面体和八面体结构的混合物，在不同条件下，Zn-O键长在0.197 - 0.203 nm范围内变化，配位数在4.3至3.2之间变化。Zn(II)初始浓度和初始pH值的增加会降低Zn-O的配位数。酵母活细胞的Zn-O键长和配位数低于死细胞。