Insights into Hydrocarbon-rich Environments from Studies of Protein Dynamics, Thermodynamics, and Spectroscopy

Abstract:

Extraordinary amounts of information are now available from genomic and metagenomic analyses of a wide variety of environments of geological and biological interest. Using such genomic information as a starting point, we are interested in looking at microbial systems at the molecular level, using the tools and approaches of inorganic chemistry, physical chemistry, and molecular biology. From these studies, spanning the molecular to the global, we gain insights into relationships between microbial life and the geochemical environment in which it lives. In our work to date, we have focused on hydrocarbon-rich environments, including the La Brea Tar Pits and the Gulf of Mexico. Starting from genomic information, we have identified proteins of interest, cloned synthetic genes into E. coli, overexpressed and purified the proteins, and characterized them by UV-visible absorption, circular dichroism, and NMR spectroscopies; X-ray crystallography; and electrochemistry. Using as examples our recent studies of a metal-uptake protein from a methanogenic archaeon native to the La Brea Tar Pits, and of electron-transfer and hydrocarbon-degrading proteins from cold marine ecosystems, we describe how new combinations of genomics, molecular biology, and bioinorganic chemistry can provide novel insights into geobiological processes.