Biddle
Jennifer F.
Biddle
Jennifer F.
No Thumbnail Available
Search Results
Now showing
1 - 6 of 6
-
ArticleDeep subsurface microbiology : a guide to the research topic papers(Frontiers Media, 2013-05-16) Teske, Andreas ; Biddle, Jennifer F. ; Edgcomb, Virginia P. ; Schippers, AxelDeep subsurface microbiology is a rising field in geomicrobiology, environmental microbiology and microbial ecology that focuses on the molecular detection and quantification, cultivation, biogeographic examination, and distribution of bacteria, archaea, and eukarya that permeate the subsurface biosphere. The deep biosphere includes a variety of subsurface habitats, such as terrestrial deep aquifer systems or mines, deeply buried hydrocarbon reservoirs, marine sediments and the basaltic ocean crust. The deep subsurface biosphere abounds with uncultured, only recently discovered and—at best—incompletely understood microbial populations. So far, microbial cells and DNA remain detectable at sediment depths of more than 1 km and life appears limited mostly by heat in the deep subsurface. Severe energy limitation, either as electron acceptor or donor shortage, and scarcity of microbially degradable organic carbon sources are among the evolutionary pressures that may shape the genomic and physiological repertoire of the deep subsurface biosphere. Its biogeochemical importance in long-term carbon sequestration, subsurface elemental cycling and crustal aging, is a major focus of current research at the interface of microbiology, geochemistry, and biosphere/geosphere evolution.
-
PreprintGene expression in the deep biosphere( 2013-04-23) Orsi, William D. ; Edgcomb, Virginia P. ; Christman, Glenn D. ; Biddle, Jennifer F.Scientific ocean drilling has revealed a deep biosphere of widespread microbial life in sub-seafloor sediment. Microbial metabolism in the marine subsurface likely plays an important role in global biogeochemical cycles1-3 but deep biosphere activities are not well understood1. Here, we describe and analyze the first subseafloor metatranscriptomes from anaerobic Peru Margin sediment up to 159 meters below seafloor (mbsf) represented by over 1 billion cDNA sequence reads. Anaerobic metabolism of amino acids, carbohydrates, and lipids appear to be dominant metabolic processes, and profiles of dissimilatory sulfite reductase (Dsr) transcripts are consistent with porewater sulfate concentration profiles1. Moreover, transcripts involved in cell division increase as a function of microbial cell concentration, indicating that increases in subseafloor microbial abundance are a function of cell division across all three domains of life. These data support calculations1 and models4 of subseafloor microbial metabolism and represent the first holistic picture of deep biosphere activities.
-
ArticleMicrobial activity in the marine deep biosphere : progress and prospects(Frontiers Media, 2013-07-11) Orcutt, Beth N. ; LaRowe, Douglas E. ; Biddle, Jennifer F. ; Colwell, Frederick S. ; Glazer, Brian T. ; Kiel Reese, Brandi ; Kirkpatrick, John B. ; Lapham, Laura L. ; Mills, Heath J. ; Sylvan, Jason B. ; Wankel, Scott D. ; Wheat, C. GeoffreyThe vast marine deep biosphere consists of microbial habitats within sediment, pore waters, upper basaltic crust and the fluids that circulate throughout it. A wide range of temperature, pressure, pH, and electron donor and acceptor conditions exists—all of which can combine to affect carbon and nutrient cycling and result in gradients on spatial scales ranging from millimeters to kilometers. Diverse and mostly uncharacterized microorganisms live in these habitats, and potentially play a role in mediating global scale biogeochemical processes. Quantifying the rates at which microbial activity in the subsurface occurs is a challenging endeavor, yet developing an understanding of these rates is essential to determine the impact of subsurface life on Earth's global biogeochemical cycles, and for understanding how microorganisms in these “extreme” environments survive (or even thrive). Here, we synthesize recent advances and discoveries pertaining to microbial activity in the marine deep subsurface, and we highlight topics about which there is still little understanding and suggest potential paths forward to address them. This publication is the result of a workshop held in August 2012 by the NSF-funded Center for Dark Energy Biosphere Investigations (C-DEBI) “theme team” on microbial activity (www.darkenergybiosphere.org).
-
ArticleHeterotrophic Archaea dominate sedimentary subsurface ecosystems off Peru(National Academy of Sciences, 2006-02-27) Biddle, Jennifer F. ; Lipp, Julius S. ; Lever, Mark A. ; Lloyd, Karen G. ; Sorensen, Ketil B. ; Anderson, Rika E. ; Fredricks, Helen F. ; Elvert, Marcus ; Kelly, Timothy J. ; Schrag, Daniel P. ; Sogin, Mitchell L. ; Brenchley, Jean E. ; Teske, Andreas ; House, Christopher H. ; Hinrichs, Kai-UweStudies of deeply buried, sedimentary microbial communities and associated biogeochemical processes during Ocean Drilling Program Leg 201 showed elevated prokaryotic cell numbers in sediment layers where methane is consumed anaerobically at the expense of sulfate. Here, we show that extractable archaeal rRNA, selecting only for active community members in these ecosystems, is dominated by sequences of uncultivated Archaea affiliated with the Marine Benthic Group B and the Miscellaneous Crenarchaeotal Group, whereas known methanotrophic Archaea are not detectable. Carbon flow reconstructions based on stable isotopic compositions of whole archaeal cells, intact archaeal membrane lipids, and other sedimentary carbon pools indicate that these Archaea assimilate sedimentary organic compounds other than methane even though methanotrophy accounts for a major fraction of carbon cycled in these ecosystems. Oxidation of methane by members of Marine Benthic Group B and the Miscellaneous Crenarchaeotal Group without assimilation of methane–carbon provides a plausible explanation. Maintenance energies of these subsurface communities appear to be orders of magnitude lower than minimum values known from laboratory observations, and ecosystem-level carbon budgets suggest that community turnover times are on the order of 100–2,000 years. Our study provides clues about the metabolic functionality of two cosmopolitan groups of uncultured Archaea.
-
ArticleThe Guaymas Basin hiking guide to hydrothermal mounds, chimneys, and microbial mats : complex seafloor expressions of subsurface hydrothermal circulation(Frontiers Media, 2016-02-18) Teske, Andreas ; de Beer, Dirk ; McKay, Luke J. ; Tivey, Margaret K. ; Biddle, Jennifer F. ; Hoer, Daniel ; Lloyd, Karen G. ; Lever, Mark A. ; Røy, Hans ; Albert, Daniel B. ; Mendlovitz, Howard P. ; MacGregor, Barbara J.The hydrothermal mats, mounds, and chimneys of the southern Guaymas Basin are the surface expression of complex subsurface hydrothermal circulation patterns. In this overview, we document the most frequently visited features of this hydrothermal area with photographs, temperature measurements, and selected geochemical data; many of these distinct habitats await characterization of their microbial communities and activities. Microprofiler deployments on microbial mats and hydrothermal sediments show their steep geochemical and thermal gradients at millimeter-scale vertical resolution. Mapping these hydrothermal features and sampling locations within the southern Guaymas Basin suggest linkages to underlying shallow sills and heat flow gradients. Recognizing the inherent spatial limitations of much current Guaymas Basin sampling calls for comprehensive surveys of the wider spreading region.
-
ArticleDeep sequencing of subseafloor eukaryotic rRNA reveals active fungi across marine subsurface provinces(Public Library of Science, 2013-02-13) Orsi, William D. ; Biddle, Jennifer F. ; Edgcomb, Virginia P.The deep marine subsurface is a vast habitat for microbial life where cells may live on geologic timescales. Because DNA in sediments may be preserved on long timescales, ribosomal RNA (rRNA) is suggested to be a proxy for the active fraction of a microbial community in the subsurface. During an investigation of eukaryotic 18S rRNA by amplicon pyrosequencing, unique profiles of Fungi were found across a range of marine subsurface provinces including ridge flanks, continental margins, and abyssal plains. Subseafloor fungal populations exhibit statistically significant correlations with total organic carbon (TOC), nitrate, sulfide, and dissolved inorganic carbon (DIC). These correlations are supported by terminal restriction length polymorphism (TRFLP) analyses of fungal rRNA. Geochemical correlations with fungal pyrosequencing and TRFLP data from this geographically broad sample set suggests environmental selection of active Fungi in the marine subsurface. Within the same dataset, ancient rRNA signatures were recovered from plants and diatoms in marine sediments ranging from 0.03 to 2.7 million years old, suggesting that rRNA from some eukaryotic taxa may be much more stable than previously considered in the marine subsurface.