Metalloregulatory proteins bacteria

An intriguing problem about which we know very little is the mechanism of metal identification by the body that triggers Its response, as in the case of the huild-up of metallothioneins upon exposure to toxic metals. Perhaps the best understood of the metalloregulatory proteins is MerR that protects bacteria from mercurial toxicity. It is extremely sensitive to Hg, and distinguishes it from its congeners Zn and Cd. There is good evidence that the mercury receptor forms three-coordinate mercury(II) complexes (see Fig. 12.1c), making possible this specificity. ... 

S-oxidizing bacteria), many are probably most appropriate for ex situ use in bioreactors, where the mobilized or immobilized metal can be separated from soil components (White et al., 1998). Living or dead fungal and bacterial biomass and metabolites have been used to remove metals, radionuclides, and metalloids from solution by biosorption or chelation (Macaskie, 1991 Gadd, 2001). The metalloregulatory protein MerR, which exhibits high affinity and selectivity toward mercury, was exploited for the construction of microbial biosorbents specific for mercury removal (Bae et ah, 2001, 2002, 2003). Whole-cell sorbents... 

---