RAPID: DEBI-t: development of a Deep Exploration Biosphere Investigative Tool

University Of Southern California, Los Angeles CA

Investigators

Abstract

Understanding the distribution of deep life in the subsurface biosphere is a major challenge to advancing our understanding of the evolution life and ecosystems on Earth. To date, all methods developed to detect microbial life in the deep biosphere involve ex-situ analysis of recovered materials from boreholes. Materials are analyzed for microbial biomass by extracting cells or cellular components, or by application of dyes to samples and performing cell counts. This latter methodology being the most standard in the industry, and represents a very time and labor intensive hands-on by eye counting of fluorescent cells under a microscope. Current methods are highly laborious and inefficient processes that involve both cell loss and the loss of information about the mineralogical context that may have influence on the microbial ecology. To meet the challenges associated with detecting and quantifying microbial life within a natural matrix, The PI requests RAPID funding to develop a novel in-situ downhole logging tool for detecting microbial life in subseafloor boreholes. "Deep UV" (DUV) is an optical method that enables detection and imaging of single bacterial cells on natural and opaque surfaces, including assessment of bacterial density and distribution of single cells to biofilms over spatial scales ranging from centimeters to microns. DUV induces and detects native fluorescence (DUV) of organic components intrinsic to the cell or spore while avoiding autofluorescence interference from the substrate, enabling detection of bacteria at spatial scales ranging from tens of centimeters to micrometers - i.e., both communities of microbes and single cells. Broader Impacts This project Leverages $350K from outside sources. It is anticipated that this technology could become widely used as a tool for detection and mapping of subsurface remote life everywhere it may occur, becoming the "satellite imager" applicable to distal environments such as represented by the entire deep sea. A JPL/Caltech post-doc with expertise in microbial physiology and fluorescence spectroscopy will be supported.