[Interaction of bacteria with mercuric compounds].

We investigated the interaction of mercuric compounds with the bacteria Corynebacterium ammoniagenes, Micrococcus luteus, and Mycobacterium smegmatus capable of producing hydroxylamines (R-NOH) and 2-C-methyl-D-erythritol-2,4-cyclopyrophosphate (MECP), which are prone to form free radicals. The interaction of these substances with Hg2+ ions and their dynamics during the mercuric poisoning of bacteria was studied by EPR and NMR. Under stress conditions induced by lowering pH or generation of active oxygen species, the bacteria and, especially, their mutants with enhanced sensitivity to oxidative stress, were found to respond to exposure to 1-3 micrograms/ml HgCl2 and p-chloromercuribenzoate by a several-fold increase in their viability. The data obtained were interpreted in terms of the involvement of the sulfhydryl groups of bacterial surface proteins in this phenomenon. The interaction of bacteria with mercuric compounds may affect the pathogenesis of tuberculosis and other diseases.