Microbial community structure across fluid gradients in the Juan de Fuca Ridge hydrothermal system

• Published in: FEMS microbiology ecology Vol. 83; no. 2; pp. 324 - 339
• Main Authors: Anderson, Rika E., Beltrán, Mónica Torres, Hallam, Steven J., Baross, John A.
• Format: Journal Article
• Language: English
• Published: Oxford, UK Blackwell Publishing Ltd 01-02-2013; Blackwell; Oxford University Press
• Subjects: Animal and plant ecology; Animal, plant and microbial ecology; Archaea - classification; Archaea - genetics; Archaea - isolation & purification; Bacteria - classification; Bacteria - genetics; Bacteria - isolation & purification; Biodiversity; Biogeochemistry; Biological and medical sciences; Community structure; Ecology; Ecosystem; Fluids; Fundamental and applied biological sciences. Psychology; High temperature; hydrothermal plume; hydrothermal vent; Hydrothermal Vents - microbiology; Microbial activity; Microbial ecology; Microbiology; Particular ecosystems; Phylogeny; Plumes; Polymorphism, Restriction Fragment Length; RNA, Ribosomal, 16S - genetics; Seawater; Seawater - microbiology; Sulfur; SUP05; Synecology; Various environments (extraatmospheric space, air, water); SUP05; hydrothermal vent; hydrothermal plume; Marine environment; Hydrothermal vent; Community structure; Juan de Fuca Ridge; Plume; Microbial community
• ISSN: 0168-6496; 1574-6941
• DOI: 10.1111/j.1574-6941.2012.01478.x

Abstract
Physical and chemical gradients are dominant factors in shaping hydrothermal vent microbial ecology, where archaeal and bacterial habitats encompass a range between hot, reduced hydrothermal fluid and cold, oxidized seawater. To determine the impact of these fluid gradients on microbial communities inhabiting these systems, we surveyed bacterial and archaeal community structure among and between hydrothermal plumes, diffuse flow fluids, and background seawater in several hydrothermal vent sites on the Juan de Fuca Ridge using 16S rRNA gene diversity screening (clone libraries and terminal restriction length polymorphisms) and quantitative polymerase chain reaction methods. Community structure was similar between hydrothermal plumes and background seawater, where a number of taxa usually associated with low-oxygen zones were observed, whereas high-temperature diffuse fluids exhibited a distinct phylogenetic profile. SUP05 and Arctic96BD-19 sulfur-oxidizing bacteria were prevalent in all three mixing regimes where they exhibited overlapping but not identical abundance patterns. Taken together, these results indicate conserved patterns of redox-driven niche partitioning between hydrothermal mixing regimes and microbial communities associated with sinking particles and oxygen-deficient waters. Moreover, the prevalence of SUP05 and Arctic96BD-19 in plume and diffuse flow fluids indicates a more cosmopolitan role for these groups in the ecology and biogeochemistry of the dark ocean.