My research seeks to address geologically informed hypotheses to unravel the biogeochemical co-evolution of Life and Earth. Specifically, I employ extant photosynthetic autotrophs, both cyanobacteria and algae, to probe the evolution of metalloenzymes and their related biochemical pathways. This type of inquiry bridges biology, chemistry, and geology. Currently, the questions driving my research include:
*Did trace metal availability as driven by changes in oxygen support the dominance of cyanobacteria during a substantial amount of Earth’s early history?
*How did the redox conditions of the environment, and thus micronutrient availability, help drive the rise of photosynthetic eukaryotes? Furthermore, why was there a push towards complex eukaryotic life?
*What biogeochemically significant metals are important to aquatic photosynthesis today?
*How does the expression and utilization of metalloenzymes vary among microorganisms?
*Does life need metals?
This talk will focus on three projects I am involved with that address different aspect of these questions. My examples will include: 1) the significance of Mn to modern and Mesozoic diatoms, 2) cyanobacteria, nitrogen assimilation and the variability of Mo during the Mid-Proterozoic and 3) the affect of Fe and Cu dynamics on life during the Paleoproterozoic. I will also briefly identify my other projects of interest to the Astrobiology community.