Response of Cupriavidus metallidurans CH34 to metals

Cupriavidus metallidurans CH34 displays resistance to a plethora of metals. Its response and underlying genetic determinants are dissected and detailed metal by metal (from arsenic to zinc). An important role for its megaplasmids pMOL28 and pMOL30 is shown, with high level resistance to cadmium, chromate, cobalt, copper, mercury, nickel, lead and zinc mediated by well-known genes for detoxification often accompanied by other functions linked to acute or chronic stress. Nevertheless, metal resistance determinants are also found on the chromid (e.g. to chromate, copper and zinc) as well as on a large genomic island integrated in the chromosome (e.g. to cadmium, lead and mercury), even the core genome participates in certain responses such as to gold or selenium. Next, we summarized the environmental applications, which were developed based on the knowledge gained by studying these different determinants, and in particular biosensors and soil and water bioremediation. Finally, the general transcriptional response of C. metallidurans to sixteen different metals supplied at different concentrations (including acute stress) is discussed within the framework of its intricate regulatory network