UVC Irradiation Induces Time-Dependent Proteomic Remodeling in Geodermatophilus obscurus G20

Geodermatophilus obscurus G20 is a multi-resistant extremophile observed to survive significant dosages of ultraviolet (UV) radiation. Despite previous work having measured G. obscurus G20s proteome in relation to its genome sequence, its proteomic response to stressors has yet to be explored. This study utilizes bottom-up proteomics with data independent acquisition to derive comprehensive proteomic measurements in both healthy and two UV-stressed conditions induced through 254 nm UV radiation administered at a median lethal dose. The first, an acute response treatment group, was recovered and flash-frozen immediately after UV radiation. The second, a recovery response treatment group, was allowed to incubate for 1 hour following UV radiation. Gene enrichment analysis revealed an increase in NADH dehydrogenase activity among both stressed treatment groups, however the recovery response treatment group experienced additional changes including reduced peptidoglycan synthesis and increased translational activity. Results suggest that the repair process undergone by G. obscurus G20 persists well after initial UV exposure and is likely to be inducing noteworthy energetic demands to facilitate UV induced genomic repair. Proteomic analyses revealed patterns that advance our mechanistic and temporal understanding of the G. obscurus metabolic response to UV irradiation.