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Environmental stresses select for suitably adapted genes. These stresses will promote the propagation of certain mutations, and the loss of others, throughout the evolution of a species. For organisms living two thousand meters below the ocean’s surface, one of these stresses is certainly high barometric pressure. Due to the imino ring structure of proline it was hypothesized that bacteria sampled from greater depths would show a larger proportion of content in their proteins. This hypothesis was examined by analyzing the proline content of 6 proteins common to 3 species from the altereythrobacter speciesl All the selected strains are Gram negative, moderately halophilic marine bacteria with optimum temperatures around 30⁰C. A. marensis strain KCTC22370 (taxonomy ID: 543877) was sampled, and genomically annotated, by Soo and Lee from the surface of the sea near Jeju island in the Republic of North Korea (2010). A. epoxidivorans strain JCS350 (taxonomy ID: 361183) was sampled from cold-seep sediment in the Kagoshima Bay, off the coast of Japan, at an approximate depth of 120m. The strain was isolated and genomically annotated by Kwon et.al. (2007). A. atlanticus strain 26DY36 (taxonomy ID: 1267766) was sampled from a North Atlantic mid ocean range at a depth of 2577m. The strain was isolated and annotated by Wu et. al. (2015). The data showed no significant differences in the proline content of the 3 species examined, however a more expansive study would be required to fully reject the hypothesis.
This study was done as part of an undergraduate molecular genetics project at the University of British Columbia Okanagan campus. The article is written in Brevia format and is meant to serve as a precursor to a future, more expansive research project, into the proline content of marine microoganisms.