SRA

Microbial resistance to cellular damage under extreme conditions is an important part of understanding the limits of life; however, the mechanisms and genetics of resistance phenotypes are poorly understood. Extraterrestrial bodies such as Mars and Europa have extreme environmental conditions that include high UV or ionizing radiation, as well as low temperature, water availability, and atmospheric pressure. The closest analog to this combination of conditions on Earth is found in the high atmosphere. Accordingly, we have characterized bacteria isolated from samples collected in the stratosphere and demonstrated many of the isolates have extreme resistance to UVC and desiccation. The overall goal of this work is to characterize the molecular genetics and mechanisms of resistance to extreme stressors in Gram positive and negative isolates recovered from 21 to 26 km above Earth's surface.