细菌抗汞分子机制与进化的研究及应用

Study and Application of Bacterial Mercury-resistance Mechanism and Evolution

微生物中存在一类抗汞细菌,操纵子Mer中的MerRTPA参与细菌抗汞的调控、转运及还原。汞通过MerTP所表达的蛋白由细胞外转运至细胞内,经还原酶MerA将其还原为毒性小的可挥发的金属汞。细菌抗汞基因的形成有着古老的起源,基因间的整合、转移进化形成了Mer操纵子结构与功能的多样性。抗汞细菌对汞的吸附具有高选择性及专一性,可利用此特性对汞污染环境进行修复,也可作为分子遗传操作中稳定的抗性筛选标记。

There exist a number of mercury-resistant bacterial in environment, Mer operen is involved in the resistant mechanism, MerRTPA of Mer operon encodes the proteins related to the regulation, transport and reduction of mercury ion, respectively. The toxic mercury ion is transported by MerTP from medium to cytoplasmic mercuric reductase, MerA, and deoxidized to non-toxic and volatile element mercury, Hg （0） . Bacterial mercury-resistant system originated from ancient times, and evolved into the Mer operen with diversity by gene integration and insertion. Mercury-resistant bacteria highly specifically absorb mercury ion, and can be used in recovering the mercury-polluted environment as weU as the genetic selective marker.