Present address: Department of Geological Sciences, University of Michigan, 1100 N. University Avenue, Ann Arbor, MI 48109-1005, USA;
Microbial diversity and biogeochemistry of the Guaymas Basin deep-sea hydrothermal plume
Article first published online: 25 FEB 2010
© 2010 Society for Applied Microbiology and Blackwell Publishing Ltd
Volume 12, Issue 5, pages 1334–1347, May 2010
How to Cite
Dick, G. J. and Tebo, B. M. (2010), Microbial diversity and biogeochemistry of the Guaymas Basin deep-sea hydrothermal plume. Environmental Microbiology, 12: 1334–1347. doi: 10.1111/j.1462-2920.2010.02177.x
- Issue published online: 23 APR 2010
- Article first published online: 25 FEB 2010
- Received 5 May, 2009; accepted 25 December, 2009.
Hydrothermal plumes are hot spots of microbial biogeochemistry in the deep ocean, yet little is known about the diversity or ecology of microorganisms inhabiting plumes. Recent biogeochemical evidence shows that Mn(II) oxidation in the Guaymas Basin (GB) hydrothermal plume is microbially mediated and suggests that the plume microbial community is distinct from deep-sea communities. Here we use a molecular approach to compare microbial diversity in the GB plume and in background deep seawater communities, and cultivation to identify Mn(II)-oxidizing bacteria from plumes and sediments. Despite dramatic differences in Mn(II) oxidation rates between plumes and background seawater, microbial diversity and membership were remarkably similar. All bacterial clone libraries were dominated by Gammaproteobacteria and archaeal clone libraries were dominated by Crenarchaeota. Two lineages, both phylogenetically related to methanotrophs and/or methylotrophs, were consistently over-represented in the plume. Eight Mn(II)-oxidizing bacteria were isolated, but none of these or previously identified Mn(II) oxidizers were abundant in clone libraries. Taken together with Mn(II) oxidation rates measured in laboratory cultures and in the field, these results suggest that Mn(II) oxidation in the GB hydrothermal plume is mediated by genome-level dynamics (gene content and/or expression) of microorganisms that are indigenous and abundant in the deep sea but have yet to be unidentified as Mn(II) oxidizers.