Tornatore, L., Borgani, S., Dolag, K. and Matteucci, F. (2007). Chemical enrichment of galaxy clusters from hydrodynamical
simulations. MNRAS, 382:1050–1072. AZD1152 molecular weight Vladilo, G. (2004). Dust and planet formation in the early Universe. In Seckbach, J. et al., editors, Life in the Universe, pages 167–168, Kluwer Academic Publishers E-mail: vladilo@oats.inaf.it Adaptability of Bacillus subtilis 168 Cells to High UV Stress Marko Wassmann, Ralf Moeller, Günther Reitz, Petra Rettberg German Aerospace Center (DLR), Institute of Aerospace Medicine, Radiation Biology Department, Research Group Photo- and Exobiology, Linder Hoehe, D-51147 Cologne, Germany Previous experiments have shown that vegetative cells of Bacillus subtilis are capable to repair large amounts of DNA photolesions directly after irradiation. But no DNA repair process is error-free, leading to mutations which will be inherited to the following generations (Sung et al., 2003). In a precursory study for the space experiment ADAPT (Molecular adaptation strategies of microorganisms selleck chemicals llc to different space and planetary UV climate conditions)*, cells of Bacillus subtilis 168 were continuously cultured under periodical 16.8 kJ/m2-polychromatic UV irradiation
at 200–400 nm (Wasserman et al., 2007). Approximately 700 generations of B. subtilis had been periodically exposed to UV radiation. Cells evolved under UV stress were 3-fold more resistant to UV-C compared to the ancestral and equally evolved but not UV-irradiated populations. Spores of both cell types respond similar to UV irradiation and exhibit ancestor UV survival characteristics. UV-evolved cells were 7-fold more resistant to ionizing radiation than their non-UV exposed
evolved relatives and ancestor, whereas no changes in the spore survival after ionizing radiation exposure of all three populations were detectable. Current investigations on the molecular mechanisms, e.g. transcriptional profiling, will allow understanding changes on the adaptation level. Sung, H. M., Yeamans, G., Ross, C. A., and Yasbin, R. E. (2003). Roles of YqjH and YqjW, homologs of the Escherichia next coli UmuC/DinB or Y superfamily of DNA polymerases, in stationary-phase mutagenesis and UV-induced mutagenesis of Bacillus subtilis. J. Bacteriol., 185:2153–2160. Wassmann, M., Moeller, R., Nellen, J., Reitz, G., Rabbow, E., and Rettberg, P. (2007). Bacillus subtilis’ ability to adapt to extreme UV stress. Int. J. Astrobiol., 6:71. *NASA homepage—Exposure Experiment (Expose/ADAPT) http://www.nasa.gov/mission_pages/station/science/experiments/Expose.html E-mail: Marko.Wassmann@dlr.de Historical and Philosophycal Aspects Santiago Ramón y Cajal and His Endosymbiotic Metastructures Within Neurons Ulises Iturbe1,3, Juli Peretó2, Antonio Lazcano1 1Facultad de Ciencias, UNAM. Apartado Postal 70-407, Cd. Universitaria, Mexico, D.