CONICET | Buscador de Institutos y Recursos Humanos

Introduction: Halophile archaeabacteria inhabits in environments with high salt concentrations (3.4-5.1 M NaCl). They are relevant to astrobiological studies because are known inhabitants of halites and ancient evaporites in Earth, structures who were detected in Martian meteorites, so halophiles are proposed as plausible inhabitants of Mars-like planets or other extrasolar planets. Terrestrial planets around dM stars can be suitable places for the emergence and evolution of life and many of these stars emit large amount of UV radiation. Objectives: we examine UV-C effects on Natrialba magadii an haloalkalophile archaea to evaluate how these UV events can influence life development. Materials and Methods:N. magadii cultures were grown at mid-exponential phase (37 °C, rich media). Culture was diluted to reach OD600nm= 0.05 and drops placed in Petri dishes. Samples were divided in groups: Non-irradiated, irradiated for 5, 10, 20, and 30 minutes. Results: OD values for each sample were obtained at different times after irradiation and plotted versus post-irradiation time. Our results show that there is a dose dependent delay in the growth of the different groups. Discussion: absence of growth for more than 30 hours, are probably attributable to t-RNA or DNA UV-related damage. Even after UV damage, the surviving cells were able to resume growth with nearly normal kinetics.

enviar mensaje