Lack of correlation of desiccation and radiation tolerance in microorganisms from diverse extreme environments tested under anoxic conditions

Kristina Beblo-Vranesevic, Maria Bohmeier, Alexandra K Perras, Petra Schwendner, Elke Rabbow, Christine Moissl-Eichinger, Charles S Cockell, Pauline Vannier, Viggo T Marteinsson, Euan P Monaghan, Pascale Ehrenfreund, Laura Garcia-Descalzo, Felipe Gómez, Moustafa Malki, Ricardo Amils, Frédéric Gaboyer, Frances Westall, Patricia Cabezas, Nicolas Walter, Petra Rettberg. 2018. Lack of correlation of desiccation and radiation tolerance in microorganisms from diverse extreme environments tested under anoxic conditions. Fems Microbiology Letters 365, 6, DOI: 10.1093/femsle/fny044

Four facultative anaerobic and two obligate anaerobic bacteria were isolated from extreme environments (deep subsurface halite mine, sulfidic anoxic spring, mineral-rich river) in the frame MASE (Mars Analogues for Space Exploration) project. The isolates were investigated under anoxic conditions for their survivability after desiccation up to 6 months and their tolerance to ionizing radiation up to 3000 Gy. The results indicated that tolerances to both stresses are strain-specific features. Yersinia intermedia MASE-LG-1 showed a high desiccation tolerance but its radiation tolerance was very low. The most radiation-tolerant strains were Buttiauxella sp. MASE-IM-9 and Halanaerobium sp. MASE-BB-1. In both cases, cultivable cells were detectable after an exposure to 3 kGy of ionizing radiation, but cells only survived desiccation for 90 and 30 days, respectively. Although a correlation between desiccation and ionizing radiation resistance has been hypothesized for some aerobic microorganisms, our data showed that there was no correlation between tolerance to desiccation and ionizing radiation, suggesting that the physiological basis of both forms of tolerances is not necessarily linked. In addition, these results indicated that facultative and obligate anaerobic organisms living in extreme environments possess varied species-specific tolerances to extremes.

Otras publicaciones

Este sitio web utiliza cookies para garantizar que obtenga la mejor experiencia en nuestro sitio web.