Interactions between microorganisms and heavy metals

摘要

Many sediments in coastal waters are contaminated with various metals. Microorganisms in these sediments can exert great influence on the bioavailability of metal compounds. The European Union project TREAD (Transport, REActions and Dynamics of heavy metals in marine sediments) aims to identify the physical, chemical and biological parameters influencing heavy metal mobility. This paper is focusing on the microorganisms that play a role in the transformations of heavy metals in marine sediments. The typical characteristics of heavy metal compounds are introduced, followed by a discussion on their toxic effects and the strategies microbes employ in order to gain a certain level of resistance. Possible interactions between microbe and metal within marine sediments are considered, including the decomposition of organic matter, reduction and re-oxidation of metal oxides, as well as the formation of sulfides. Subsequently, the TREAD project is described in more detail followed by a discussion of comparable studies. This paper is concluded with an overview of the experimental tools that will be applied to study the microorganisms involved in heavy metal transformations'.