The physiological role and biochemical mechanism of bacterial manganese(II) oxidation
As one of the most abundant transition metals in the earth's crust, manganese is prevalent in biological systems. It is found in superoxide dismutase, the oxygen evolving complex of photosystem II, and it plays an important role in biogeochemical cycling of carbon, sulfur, and several trace elements. Some microbes can even oxidize Mn(II), transforming it to Mn(III) and Mn(IV) oxides. Although bacterial Mn(II) oxidation is thought to be ubiquitous in nature, its physiological role remains poorly understood. Recently, researchers identified two putative Mn(II) oxidase genes, mnxG and mcoA, in the organisms Pseudomonas putida GB-1 and Bacillus sp. SG-1. The proteins are predicted to be multicopper oxidases, a family of Cu-containing enzymes that couples oxidation of metal or organic substrates to reduction of dioxygen. This project will use a combination of molecular and spectroscopic techniques to investigate both possible physiological roles for bacterial Mn(II) oxidation, and the enzymes that mediate this process.
This research will teach the fellow a variety of biological, environmental, and chemical techniques, allowing her to pursue an independent research career after she completes her post-doctoral training. Additionally, she will volunteer with several ongoing outreach efforts in the laboratory of her sponsor. In particular, she will work with the NSF Science and Technology Center for Coastal Margin Observation and Prediction (CMOP) to provide undergraduate internships and K-12 educational programs. She will also mentor students in the laboratory and teach summer school classes through the Saturday Academy (www.saturdayacademy.org). She aims to provide young students with hands-on training in environmental microbiology.
