Gadd G M
University of Dundee.
Endeavour. 1996;20(4):150-6. doi: 10.1016/s0160-9327(96)10021-1.
Microorganisms have a significant influence on the environmental fate of radionuclides in aquatic and terrestrial ecosystems with a multiplicity of physico-chemical and biological mechanisms effecting changes in mobility and speciation. Physico-chemical mechanisms of removal include association with extracellular materials, metabolites and cell walls which are features of living and dead organisms. In living cells, some physico-chemical processes are reversible, influenced by metabolism and changing environmental conditions. Metabolism-dependent mechanisms of radionuclide immobilization include sulphide precipitation, transport and intracellular compartmentation and/or sequestration by proteins and peptides. In addition, chemical reduction to less soluble forms can result in immobilization. Microbial processes involved in radionuclide solubilization include autotrophic and heterotrophic leaching, and complexation by siderophores and other metabolites. Such mechanisms are important components of biogeochemical cycles for radionuclides and should be considered in any analyses of environmental radionuclide contamination. In addition, several microorganism-based biotechnologies are receiving interest as potential treatment methods.
微生物通过多种物理化学和生物学机制对水生和陆地生态系统中放射性核素的环境归宿产生重大影响，这些机制会影响其迁移性和形态。去除的物理化学机制包括与细胞外物质、代谢产物和细胞壁结合，这些是活的和死的生物体的特征。在活细胞中，一些物理化学过程是可逆的，受代谢和不断变化的环境条件影响。依赖代谢的放射性核素固定机制包括硫化物沉淀、运输以及通过蛋白质和肽进行细胞内区室化和/或螯合。此外，化学还原为溶解度较低的形式可导致固定。参与放射性核素溶解的微生物过程包括自养和异养浸出，以及通过铁载体和其他代谢产物进行络合。这些机制是放射性核素生物地球化学循环的重要组成部分，在任何环境放射性核素污染分析中都应予以考虑。此外，几种基于微生物的生物技术作为潜在的处理方法正受到关注。
