Manganese Oxidation and Stress Response

This week I worked on preparing plasmids containing MnxG and SOD(2) for sequencing from the TOPO clones we prepared last week. The sequencing data will be analyzed and used to confirm the presence of these genes so that the other interns can use those plasmids to investigate the effects of these proteins and others such as catalase and Oxy on thermal and oxidative stress response. One of Christine’s main projects is looking at the relationship between the ability of wild type pseudomonas Putida (who is able to oxidize manganese) and mutants with Manganese oxidizing genes knocked out to survive environmental stressors. Previous research has shown a direct correlation between increased stress response with the ability to oxidize manganese, and so far Christine’s experiments have found this to be true as well. It is unclear why exactly this is, but it is hypothesized that manganese may act as a sort of mineral catalyst that works with superoxide dismutase (SOD) to contain oxidative damage by reacting with super oxides.

I also worked with one of the post docs in my lab to carry out a kinetic assay of MnxG. This assay allowed us to measure the rate of Mn⁺² to Mn⁺⁴ oxidation using an LBB standard and change in optical density every minute. Time sensitive reactions like that are always a bit chaotic, and we had to repeat it several times before we did it correctly. I am happy that I have the opportunity to work with new people in the lab because we have several experienced post docs that each have a very specialized focus related to manganese oxidation. I’m really grateful that I have the opportunity to learn from them and ask them about their professional and educational backgrounds.