Looking at Hg distribution by nano-X-ray fluorescence to elucidate the role of a two-component sensing system and a metal efflux system in b

Methylmercury (MeHg) is a strong neurotoxin and is mainly produced by sulfate-reducing bacteria (SRB) in anoxic environments. However, the mechanisms of Hg methylation are still poorly understood. We study the model SRB strain Pseudodesulfovibrio hydrargyri BerOc1 and we have generated BerOc1 mutants impaired with a metal efflux system and with a two-component sensing system involved in Hg regulation, and probably Hg sequestration. These mutants showed specific phenotypes in Hg methylation. Our objective is to clarify the role of these genes in Hg distribution at the cell level. For that, we will image single cells from wild type and mutants by nano X-ray fluorescence (nano-XRF)