Kaitlin Harrison

Abstract Cyanobacteria are highly abundant in the marine photic zone and primary drivers of the conversion of inorganic carbon to biomass. To date, all studied Cyanobacterial lineages encode carbon fixation machinery hinged upon form I rubisco enzymes within a CO2-concentrating carboxysome.

Abstract The act of fixing inorganic carbon into the biosphere is largely facilitated by one enzyme, Rubisco. Beyond well-studied plants and cyanobacteria, many bacteria use Rubisco for chemolithoautotrophy in extreme environments on Earth. Here, we characterized the diversity of chemolithoautotrophic Rubiscos in subzero environments. First, we surveyed subzero environments and found that the Calvin-Benson-Bassham cycle was the most prevalent chemolithoautotrophic pathway.