title: Shifts in the meso- and bathypelagic archaea communities composition during recovery and short-term handling of decompressed deep-sea samples.
abstract: Dark ocean microbial communities are actively involved in chemoautotrophic and anaplerotic fixation of bicarbonate. Thus, aphotic pelagic realm of the ocean might represent a significant sink of CO2 and source of primary production. However, the estimated metabolic activities in the dark ocean are fraught with uncertainties. Typically, deep-sea samples are recovered to the sea surface for downstream processing on deck. Shifts in ambient settings, associated with such treatments, can likely change the metabolic activity and community structure of deep-sea adapted autochthonous microbial populations. To estimate influence of recovery and short-term handling of deep-sea samples, we monitored the succession of bathypelagic microbial community during its 3 days long on deck incubation. We demonstrated that at the end of exposition, the deep-sea archaeal population decreased threefold, whereas the bacterial fraction doubled in size. As revealed by phylogenetic analyses of amoA gene transcripts, dominance of the active ammonium-oxidizing bathypelagic Thaumarchaeota groups shifted over time very fast. These findings demonstrated the simultaneous existence of various 'deep-sea ecotypes', differentially reacting to the sampling and downstream handling. Our study supports the hypothesis that metabolically active members of meso- and bathypelagic Thaumarchaeota possess the habitat-specific distribution, metabolic complexity and genetic divergence at subpopulation level.
authors: Institute for Coastal Marine Environment, CNR, Spianata S. Raineri 86, 98122, Messina, Italy.
authors: Violetta
authors: V
authors: La Cono
authors: Institute for Coastal Marine Environment, CNR, Spianata S. Raineri 86, 98122, Messina, Italy.
authors: Francesco
authors: F
authors: Smedile
authors: Institute for Coastal Marine Environment, CNR, Spianata S. Raineri 86, 98122, Messina, Italy.
authors: Gina
authors: G
authors: La Spada
authors: Institute for Coastal Marine Environment, CNR, Spianata S. Raineri 86, 98122, Messina, Italy.
authors: Erika
authors: E
authors: Arcadi
authors: Institute for Coastal Marine Environment, CNR, Spianata S. Raineri 86, 98122, Messina, Italy.
authors: Maria
authors: M
authors: Genovese
authors: Institute for Coastal Marine Environment, CNR, Spianata S. Raineri 86, 98122, Messina, Italy.
authors: Gioacchino
authors: G
authors: Ruggeri
authors: Institute for Coastal Marine Environment, CNR, Spianata S. Raineri 86, 98122, Messina, Italy.
authors: Lucrezia
authors: L
authors: Genovese
authors: Institute for Coastal Marine Environment, CNR, Spianata S. Raineri 86, 98122, Messina, Italy.|Mediterranean Science Commission (CIESM), 16 bd de Suisse, Monte Carlo, 98000, Monaco.
authors: Laura
authors: L
authors: Giuliano
authors: Institute for Coastal Marine Environment, CNR, Spianata S. Raineri 86, 98122, Messina, Italy.
authors: Michail M
authors: MM
authors: Yakimov
mesh_terms: D000220:Adaptation, Biological; D001105:Archaea / Q000145:classification* / Q000302:isolation & purification* / Q000502:physiology; D058448:Biota; D003664:Decompression; D012623:Seawater / Q000382:microbiology*