Microbial Ecology and Biotechnology Branch, Environmental Research Laboratory, U.S. Environmental Protection Agency, Gulf Breeze, Florida 32561.
Appl Environ Microbiol. 1987 Dec;53(12):2725-32. doi: 10.1128/aem.53.12.2725-2732.1987.
The mechanism of adaptation to Hg in four aquatic habitats was studied by correlating microbially mediated Hg volatilization with the adaptive state of the exposed communities. Community diversity, heterotrophic activity, and Hg resistance measurements indicated that adaptation of all four communities was stimulated by preexposure to Hg. In saline water communities, adaptation was associated with rapid volatilization after an initial lag period. This mechanism, however, did not promote adaptation in a freshwater sample, in which Hg was volatilized slowly, regardless of the resistance level of the microbial community. Distribution of the mer operon among representative colonies of the communities was not related to adaptation to Hg. Thus, although volatilization enabled some microbial communities to sustain their functions in Hg-stressed environments, it was not mediated by the genes that serve as a model system in molecular studies of bacterial resistance to mercurials.
研究了四种水生栖息地适应汞的机制，方法是将微生物介导的汞挥发与暴露群落的适应状态相关联。群落多样性、异养活性和汞抗性测量表明，所有四个群落的适应都是由预暴露于汞引起的。在咸水环境中，适应与初始滞后期后快速挥发有关。然而，这种机制并没有促进淡水样本的适应，在淡水样本中，无论微生物群落的抗性水平如何，汞的挥发都很慢。在群落的代表性菌落中 mer 操纵子的分布与对汞的适应无关。因此，尽管挥发使一些微生物群落能够在汞胁迫环境中维持其功能，但它不是由作为细菌抗汞分子研究模型系统的基因介导的。
