Deuterium Oxide as a Stress Factor for the Methylotrophic Bacterium Methylophilus sp. B-7741

The adaptation of the methylotrophic bacterium Methylophilus sp. B-7741 to growth in highly deuterated media was studied. For the first time, we showed the cross adaptation of bacterial cells to deuterated media and oxidative and osmotic stresses. The activity of catalase in deuterated cells was higher than in the control cells. Deuterated cell-free culture liquids showed protective effects on the growth of Methylophilus sp. B-7741 in deuterated media, which was manifested as an increase in the deuterated biomass yield. These data and the data available in the literature suggest that the mechanisms of bacterial cell adaptation to heavy water and to oxidative and osmotic stresses are similar.