title: Large-scale distribution and activity of prokaryotes in deep-sea surface sediments of the Mediterranean Sea and the adjacent Atlantic Ocean.
abstract: The deep-sea represents a substantial portion of the biosphere and has a major influence on carbon cycling and global biogeochemistry. Benthic deep-sea prokaryotes have crucial roles in this ecosystem, with their recycling of organic matter from the photic zone. Despite this, little is known about the large-scale distribution of prokaryotes in the surface deep-sea sediments. To assess the influence of environmental and trophic variables on the large-scale distribution of prokaryotes, we investigated the prokaryotic assemblage composition (Bacteria to Archaea and Euryarchaeota to Crenarchaeota ratio) and activity in the surface deep-sea sediments of the Mediterranean Sea and the adjacent North Atlantic Ocean. Prokaryotic abundance and biomass did not vary significantly across the Mediterranean Sea; however, there were depth-related trends in all areas. The abundance of prokaryotes was positively correlated with the sedimentary concentration of protein, an indicator of the quality and bioavailability of organic matter. Moving eastwards, the Bacteria contribution to the total prokaryotes decreased, which appears to be linked to the more oligotrophic conditions of the Eastern Mediterranean basins. Despite the increased importance of Archaea, the contributions of Crenarchaeota Marine Group I to the total pool was relatively constant across the investigated stations, with the exception of Matapan-Vavilov Deep, in which Euryarchaeota Marine Group II dominated. Overall, our data suggest that deeper areas of the Mediterranean Sea share more similar communities with each other than with shallower sites. Freshness and quality of sedimentary organic matter were identified through Generalized Additive Model analysis as the major factors for describing the variation in the prokaryotic community structure and activity in the surface deep-sea sediments. Longitude was also important in explaining the observed variability, which suggests that the overlying water masses might have a critical role in shaping the benthic communities.
authors.affiliation: Institute for Marine Science - ISMAR, National Research Council of Italy - CNR, Ancona, Italy.
authors.forename: Donato
authors.initials: D
authors.lastname: Giovannelli
authors.forename: Massimiliano
authors.initials: M
authors.lastname: Molari
authors.forename: Giuseppe
authors.initials: G
authors.lastname: d'Errico
authors.forename: Elisa
authors.initials: E
authors.lastname: Baldrighi
authors.forename: Claudia
authors.initials: C
authors.lastname: Pala
authors.forename: Elena
authors.initials: E
authors.lastname: Manini
mesh_terms: D001105:Archaea / Q000302:isolation & purification*; D001267:Atlantic Ocean; D001419:Bacteria / Q000302:isolation & purification*; D018533:Biomass; D017753:Ecosystem; D004777:Environment; D005843:Geography; D019015:Geologic Sediments / Q000382:microbiology*; D008522:Mediterranean Sea; D012623:Seawater
references.citation: Proc Natl Acad Sci U S A. 2012 Oct 2;109(40):16213-6
references.pmid: 22927371
references.citation: Nat Rev Microbiol. 2007 Oct;5(10):770-81
references.pmid: 17828281
references.citation: Syst Appl Microbiol. 1999 Sep;22(3):434-44
references.pmid: 10553296
references.citation: Appl Environ Microbiol. 1998 Jul 1;64(7):2691-6
references.pmid: 9647850
references.citation: Appl Environ Microbiol. 2004 Jul;70(7):4411-4
references.pmid: 15240332
references.citation: Nature. 2005 Sep 22;437(7058):543-6
references.pmid: 16177789
references.citation: FEMS Microbiol Ecol. 2004 Nov 1;50(3):203-13
references.pmid: 19712361
references.citation: Appl Environ Microbiol. 1999 Oct;65(10):4375-84
references.pmid: 10508063
references.citation: Science. 2012 Feb 3;335(6068):587-90
references.pmid: 22301318
references.citation: Appl Environ Microbiol. 2003 May;69(5):2463-83
references.pmid: 12732511
references.citation: Environ Microbiol. 2013 May;15(5):1647-58
references.pmid: 22690844
references.citation: Environ Microbiol Rep. 2010 Oct;2(5):693-703
references.pmid: 23766257
references.citation: ISME J. 2009 Feb;3(2):231-42
references.pmid: 18843298
references.citation: Nature. 2008 Aug 21;454(7207):991-4
references.pmid: 18641632
references.citation: Proc Natl Acad Sci U S A. 2006 Aug 29;103(35):13104-9
references.pmid: 16938845
references.citation: Appl Environ Microbiol. 2002 Mar;68(3):1468-72
references.pmid: 11872504
references.citation: Proc Natl Acad Sci U S A. 1992 Jun 15;89(12):5685-9
references.pmid: 1608980
references.citation: Appl Environ Microbiol. 1990 Jun;56(6):1919-25
references.pmid: 2200342
references.citation: Science. 2004 Dec 24;306(5705):2216-21
references.pmid: 15618510
references.citation: Curr Microbiol. 2012 Mar;64(3):242-50
references.pmid: 22159570
references.citation: ISME J. 2012 Jun;6(6):1250-9
references.pmid: 22170423
references.citation: Proc Biol Sci. 2001 Feb 7;268(1464):303-9
references.pmid: 11217902
references.citation: ISME J. 2010 Feb;4(2):159-70
references.pmid: 19829317
references.citation: Int Microbiol. 2010 Sep;13(3):143-50
references.pmid: 20890848
references.citation: Appl Environ Microbiol. 2001 Jan;67(1):387-95
references.pmid: 11133470
references.citation: Environ Microbiol. 2011 Dec;13(12):3219-34
references.pmid: 21895908
references.citation: ISME J. 2011 Jun;5(6):945-61
references.pmid: 21209665
references.citation: Nature. 2002 Nov 28;420(6914):379-84
references.pmid: 12459775
references.citation: FEMS Microbiol Ecol. 2000 Aug 1;33(2):89-99
references.pmid: 10967208
references.citation: ISME J. 2009 Feb;3(2):147-58
references.pmid: 18818711
references.citation: Nature. 2008 Dec 11;456(7223):788-91
references.pmid: 19037244
references.citation: Appl Environ Microbiol. 1999 Dec;65(12):5554-63
references.pmid: 10584017
references.citation: FEMS Microbiol Ecol. 2006 Mar;55(3):416-23
references.pmid: 16466380
references.citation: Nature. 2006 Nov 16;444(7117):354-7
references.pmid: 17108962
references.citation: Nature. 2001 Jan 25;409(6819):507-10
references.pmid: 11206545
references.citation: Nat Rev Microbiol. 2005 Jul;3(7):537-46
references.pmid: 15953930
references.citation: Appl Environ Microbiol. 2005 May;71(5):2303-9
references.pmid: 15870315
references.citation: Proc Natl Acad Sci U S A. 2009 Nov 17;106(46):19211-8
references.pmid: 19901326
references.citation: Microb Ecol. 2001 Dec;42(4):549-561
references.pmid: 12024238
references.citation: Nat Rev Microbiol. 2007 Oct;5(10):782-91
references.pmid: 17853906
references.citation: Nature. 2008 Aug 21;454(7207):952-3
references.pmid: 18719578
references.citation: Nature. 2005 Feb 24;433(7028):861-4
references.pmid: 15729341
references.citation: ISME J. 2010 Feb;4(2):182-90
references.pmid: 19847207
references.citation: J Microbiol Methods. 2004 Jun;57(3):351-67
references.pmid: 15134883
references.citation: Appl Environ Microbiol. 1998 Jul;64(7):2585-95
references.pmid: 9647834
references.citation: Nature. 2008 Aug 28;454(7208):1084-7
references.pmid: 18756250
references.citation: Appl Environ Microbiol. 2002 Jun;68(6):3094-101
references.pmid: 12039771
references.citation: Appl Environ Microbiol. 2000 May;66(5):1777-87
references.pmid: 10788339
references.citation: ISME J. 2012 Aug;6(8):1566-77
references.pmid: 22258100