[Study of the horizontal transfer of mercury resistance genes in natural populations of bacteria using antibodies to mercury reductases].

Mercury resistant soil and intestinal bacteria were isolated from different mercury deposit areas of the USSR. Mercury reductases from all gram negative bacteria studied (Pseudomonas, Acinetobacter and Enterobacterial species) with a single exception (Flavobacterium sp.) were immunologically cross reactive. Two immunological types of mercury reductases were found among gram positive bacteria (Bacillus, Staphylococcus and Coryneform species). Further subdivisions were done by "spur" formation tests. Despite considerable diversity of mercury reductases revealed in this study, we found several strains which belonged to distant genera but contained immunologically indistinguishable enzymes. This suggested that the horizontal spread of the corresponding genes occurred in these genera in relatively recent time.