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ArticleLinks from mantle to microbe at the Lau Integrated Study Site : insights from a back-arc spreading center(The Oceanography Society, 2012-03) Tivey, Margaret K. ; Becker, Erin ; Beinart, Roxanne A. ; Fisher, Charles R. ; Girguis, Peter R. ; Langmuir, Charles H. ; Michael, Peter J. ; Reysenbach, Anna-LouiseThe Lau Integrated Study Site (ISS) has provided unique opportunities for study of ridge processes because of its back-arc setting in the southwestern Pacific. Its location allows study of a biogeographical province distinct from those of eastern Pacific and mid-Atlantic ridges, and crustal compositions along the ridge lie outside the range of mid-ocean ridge crustal compositions. The Lau ISS is located above a subduction zone, at an oblique angle. The underlying mantle receives water and other elements derived from the downgoing lithospheric slab, with an increase in slab influence from north to south. Water lowers the mantle melting temperature and leads to greater melt production where the water flux is greater, and to distinctive regional-scale gradients along the ridge. There are deeper faulted axial valleys with basaltic volcanism in the north and inflated axial highs with andesites in the south. Differences in igneous rock composition and release of magmatic volatiles affect compositions of vent fluids and deposits. Differences in vent fluid compositions and small-scale diffuse-flow regimes correlate with regional-scale patterns in microbial and megafaunal distributions. The interdisciplinary research effort at the Lau ISS has successfully identified linkages between subsurface processes and deep-sea biological communities, from mantle to microbe to megafauna.
PreprintA ubiquitous thermoacidophilic archaeon from deep-sea hydrothermal vents( 2006-05-19) Reysenbach, Anna-Louise ; Liu, Yitai ; Banta, Amy B. ; Beveridge, Terry J. ; Kirshtein, Julie D. ; Schouten, Stefan ; Tivey, Margaret K. ; Von Damm, Karen L. ; Voytek, Mary A.Deep-sea hydrothermal vents play an important role in global biogeochemical cycles, providing biological oases at the seafloor that are supported by the thermal and chemical flux from the Earth’s interior. As hot, acidic and reduced hydrothermal fluids mix with cold, alkaline and oxygenated seawater, minerals precipitate to form porous sulphide-sulphate deposits. These structures provide microhabitats for a diversity of prokaryotes that exploit the geochemical and physical gradients in this dynamic ecosystem. It has been proposed that fluid pH in the actively-venting sulphide structures is generally low (pH<4.5)2 yet no extreme thermoacidophile has been isolated from vent deposits. Culture-independent surveys based on rRNA genes from deep-sea hydrothermal deposits have identified a widespread euryarchaeotal lineage, DHVE23-6. Despite DHVE2’s ubiquity and apparent deep-sea endemism, cultivation of this group has been unsuccessful and thus its metabolism remains a mystery. Here we report the isolation and cultivation of a member of the DHVE2 group, which is an obligate thermoacidophilic sulphur or iron reducing heterotroph capable of growing from pH 3.3 to 5.8 and between 55 to 75°C. In addition, we demonstrate that this isolate constitutes up to 15% of the archaeal population, providing the first evidence that thermoacidophiles may be key players in the sulphur and iron cycling at deep-sea vents.
DatasetSampling overview from R/V Roger Revelle cruise RR1507 in the Eastern Lau Spreading Center in 2015 (Functional microbial dynamics of vent deposits project)(Biological and Chemical Oceanography Data Management Office (BCO-DMO). Contact: firstname.lastname@example.org, 2021-12-07) Reysenbach, Anna-Louise ; Seewald, Jeffrey SSampling overview from R/V Roger Revelle cruise RR1507 in the Eastern Lau Spreading Center in 2015. For a complete list of measurements, refer to the full dataset description in the supplemental file 'Dataset_description.pdf'. The most current version of this dataset is available at: https://www.bco-dmo.org/dataset/566965
DatasetAccession numbers for metagenome-assembled genomes (MAGs) from samples collected in 2018 on R/V Thompson cruise TN350 at the Upper and Lower Cones, Upper Caldera Wall and NW Caldera, Brothers Volcano(Biological and Chemical Oceanography Data Management Office (BCO-DMO). Contact: email@example.com, 2022-08-24) Reysenbach, Anna-Louise ; Humphris, SusanAccession numbers for metagenome-assembled genomes (MAGs) from the Upper and Lower Cones, Upper Caldera Wall and NW Caldera, Brothers Volcano. Published in Reysenbach & St. John et al., 2020. Sequence data is available in NCBI Genbank under BioProject accession PRJNA546572. For a complete list of measurements, refer to the full dataset description in the supplemental file 'Dataset_description.pdf'. The most current version of this dataset is available at: https://www.bco-dmo.org/dataset/868323
ArticleNew opportunities and untapped scientific potential in the abyssal ocean(Frontiers Media, 2022-02-03) Marlow, Jeffrey ; Anderson, Rika E. ; Reysenbach, Anna-Louise ; Seewald, Jeffrey S. ; Shank, Timothy M. ; Teske, Andreas P. ; Wanless, V. Dorsey ; Soule, S. AdamThe abyssal ocean covers more than half of the Earth’s surface, yet remains understudied and underappreciated. In this Perspectives article, we mark the occasion of the Deep Submergence Vehicle Alvin’s increased depth range (from 4500 to 6500 m) to highlight the scientific potential of the abyssal seafloor. From a geologic perspective, ultra-slow spreading mid-ocean ridges, Petit Spot volcanism, transform faults, and subduction zones put the full life cycle of oceanic crust on display in the abyss, revealing constructive and destructive forces over wide ranges in time and space. Geochemically, the abyssal pressure regime influences the solubility of constituents such as silica and carbonate, and extremely high-temperature fluid-rock reactions in the shallow subsurface lead to distinctive and potentially unique geochemical profiles. Microbial residents range from low-abundance, low-energy communities on the abyssal plains to fast growing thermophiles at hydrothermal vents. Given its spatial extent and position as an intermediate zone between coastal and deep hadal settings, the abyss represents a lynchpin in global-scale processes such as nutrient and energy flux, population structure, and biogeographic diversity. Taken together, the abyssal ocean contributes critical ecosystem services while facing acute and diffuse anthropogenic threats from deep-sea mining, pollution, and climate change.
ArticleComplex subsurface hydrothermal fluid mixing at a submarine arc volcano supports distinct and highly diverse microbial communities(National Academy of Sciences, 2020-12-04) Reysenbach, Anna-Louise ; St. John, Emily ; Meneghin, Jennifer ; Flores, Gilberto ; Podar, Mircea ; Dombrowski, Nina ; Spang, Anja ; L’Haridon, Stephane ; Humphris, Susan E. ; de Ronde, Cornel E. J. ; Tontini, F. Caratori ; Tivey, Maurice A. ; Stucker, Valerie ; Stewart, Lucy C. ; Diehl, Alexander ; Bach, WolfgangHydrothermally active submarine volcanoes are mineral-rich biological oases contributing significantly to chemical fluxes in the deep sea, yet little is known about the microbial communities inhabiting these systems. Here we investigate the diversity of microbial life in hydrothermal deposits and their metagenomics-inferred physiology in light of the geological history and resulting hydrothermal fluid paths in the subsurface of Brothers submarine volcano north of New Zealand on the southern Kermadec arc. From metagenome-assembled genomes we identified over 90 putative bacterial and archaeal genomic families and nearly 300 previously unknown genera, many potentially endemic to this submarine volcanic environment. While magmatically influenced hydrothermal systems on the volcanic resurgent cones of Brothers volcano harbor communities of thermoacidophiles and diverse members of the superphylum “DPANN,” two distinct communities are associated with the caldera wall, likely shaped by two different types of hydrothermal circulation. The communities whose phylogenetic diversity primarily aligns with that of the cone sites and magmatically influenced hydrothermal systems elsewhere are characterized predominately by anaerobic metabolisms. These populations are probably maintained by fluids with greater magmatic inputs that have interacted with different (deeper) previously altered mineral assemblages. However, proximal (a few meters distant) communities with gene-inferred aerobic, microaerophilic, and anaerobic metabolisms are likely supported by shallower seawater-dominated circulation. Furthermore, mixing of fluids from these two distinct hydrothermal circulation systems may have an underlying imprint on the high microbial phylogenomic diversity. Collectively our results highlight the importance of considering geologic evolution and history of subsurface processes in studying microbial colonization and community dynamics in volcanic environments.