Award: OCE-1851582

Earth’s seafloor consists mostly of sediment layered over a rocky basement of basalt. The fluid that flows within cracks and fissures of this basaltic rock forms our planet’s largest aquifer, and one of its largest reservoirs of microbial life. A volume of seawater equivalent to the entire global ocean circulates through this subseafloor basement every ~50 to 100,000 years. As seawater circulates through this subseafloor aquifer, it is highly altered by both abiotic water-rock interactions and microbial activity that can have large impacts on the ecology and elemental cycling of the global ocean. The environmental and chemical conditions experienced by microorganisms living in the ocean’s subsurface environment are, in many ways, similar to the conditions where we might expect to find life on other planetary bodies beyond Earth, making it an excellent analog for exploring life in such environments and conditions. While its size does not necessarily correlate with an enriched diversity of life, previous observations have revealed that the deep subseafloor biome is dominated by uncultivated, deeply branching lineages of life that harbor ancient enzymes responsible for shaping the chemical characteristics and ultimate habitability of Earth.

Through the support of this project, a team of eleven scientists from three collaborating universities participated in a research cruise to the Juan de Fuca Ridge flank in the Pacific Ocean, where unique and custom-developed technology was used to collect deep subseafloor fluids. New methods designed to isolate and grow deep subseafloor microorganisms were subsequently used to successfully grow, for the first time, microorganisms that are abundant in the deep subseafloor and other environments but have so far evaded cultivation in the laboratory. The foundation created by this project now provides scientists the opportunity to study these microorganisms in controlled experimental conditions for the first time in order to understand their ecology, evolution, and biotechnological potential.

Broader Impacts. This project provided engaging, cutting-edge research experiences to undergraduate, graduate, and postdoctoral scientists, where it incorporated junior scientists within every aspect of the project. It also increased the participation of underrepresented groups in scientific research by supporting the participation of a graduate and undergraduate student of native Hawaiian ancestry in hands-on research and training. This project also supported the careers of four early career female scientists of which all started faculty positions in 2017 or later, providing them with a supportive collaboration and new samples and analyses that are relevant to their research and career goals.

Last Modified: 08/02/2024
Modified by: Michael S Rappe