title: Iron reduction by the deep-sea bacterium Shewanella profunda LT13a under subsurface pressure and temperature conditions.
abstract: Microorganisms influence biogeochemical cycles from the surface down to the depths of the continental rocks and oceanic basaltic crust. Due to the poor recovery of microbial isolates from the deep subsurface, the influence of physical environmental parameters, such as pressure and temperature, on the physiology and metabolic potential of subsurface inhabitants is not well constrained. We evaluated Fe(III) reduction rates (FeRRs) and viability, measured as colony-forming ability, of the deep-sea piezophilic bacterium Shewanella profunda LT13a over a range of pressures (0-125 MPa) and temperatures (4-37∘C) that included the in situ habitat of the bacterium isolated from deep-sea sediments at 4500 m depth below sea level. S. profunda LT13a was active at all temperatures investigated and at pressures up to 120 MPa at 30∘C, suggesting that it is well adapted to deep-sea and deep sedimentary environments. Average initial cellular FeRRs only slightly decreased with increasing pressure until activity stopped, suggesting that the respiratory chain was not immediately affected upon the application of pressure. We hypothesize that, as pressure increases, the increased energy demand for cell maintenance is not fulfilled, thus leading to a decrease in viability. This study opens up perspectives about energy requirements of cells in the deep subsurface.
authors: Department of Biogeochemistry, Max Planck Institute for Marine Microbiology Bremen, Germany ; MARUM Center for Marine Environmental Sciences Bremen, Germany ; Center for Applied Geoscience, Eberhard Karls University Tübingen Tübingen, Germany.
authors: Aude
authors: A
authors: Picard
authors: Institut Néel, Université Grenoble Alpes Grenoble, France ; Institut Néel, Centre National de la Recherche Scientifique Grenoble, France.
authors: Denis
authors: D
authors: Testemale
authors: Department of Biogeochemistry, Max Planck Institute for Marine Microbiology Bremen, Germany.
authors: Laura
authors: L
authors: Wagenknecht
authors: Christopher Ingold Laboratory, Department of Chemistry, University College London London, UK.
authors: Rachael
authors: R
authors: Hazael
authors: CNRS, Laboratoire de Géologie de Lyon, Ecole Normale Supérieure de Lyon, Université Claude Bernard Lyon 1-Université de Lyon UMR5276, Lyon, France.
authors: Isabelle
authors: I
authors: Daniel
keywords: Fe reduction; Shewanella profunda; XANES; pressure; temperature
references: Gene. 2005 Feb 14;346:1-6
references: 15716096
references: Annu Rev Phys Chem. 1993;44:89-113
references: 8257561
references: BMC Microbiol. 2008 Jan 23;8:13
references: 18215278
references: Nat Rev Microbiol. 2013 Feb;11(2):83-94
references: 23321532
references: Biophys Chem. 2013 Dec 15;183:30-41
references: 23891571
references: J Bacteriol. 2009 Apr;191(8):2574-84
references: 19201790
references: Appl Environ Microbiol. 2004 Feb;70(2):1231-3
references: 14766611
references: Biosci Biotechnol Biochem. 2012;76(8):1506-10
references: 22878211
references: Geobiology. 2011 Mar;9(2):196-204
references: 21231995
references: J Synchrotron Radiat. 2006 Jan;13(Pt 1):59-68
references: 16371709
references: Front Microbiol. 2012 Jul 17;3:253
references: 22822404
references: Environ Microbiol. 2009 Dec;11(12):3140-53
references: 19694787
references: FEMS Microbiol Lett. 2007 Feb;267(1):108-12
references: 17166225
references: J Biotechnol. 2006 Oct 20;126(1):11-25
references: 16780980
references: Int J Syst Bacteriol. 1999 Apr;49 Pt 2:705-24
references: 10319494
references: Nat Rev Microbiol. 2008 Aug;6(8):592-603
references: 18604222
references: Extremophiles. 1998 Aug;2(3):149-54
references: 9783159
references: Biochim Biophys Acta. 2002 Mar 25;1595(1-2):367-81
references: 11983409
references: FEMS Microbiol Ecol. 2001 May;35(3):223-230
references: 11311432
references: J Synchrotron Radiat. 2005 Jul;12(Pt 4):537-41
references: 15968136
references: Microbiol Rev. 1995 Mar;59(1):143-69
references: 7535888
references: Appl Environ Microbiol. 1977 Apr;33(4):885-92
references: 405925
references: Int J Syst Evol Microbiol. 2004 Nov;54(Pt 6):1943-9
references: 15545415
references: Geobiology. 2013 Nov;11(6):593-601
references: 24102974
references: Science. 1985 May 31;228(4703):1101-3
references: 3992247
references: Annu Rev Microbiol. 1995;49:777-805
references: 8561479
references: Science. 2004 Dec 24;306(5705):2216-21
references: 15618510
references: PLoS One. 2008 Apr 09;3(4):e1937
references: 18398463
references: Trends Microbiol. 2010 Sep;18(9):413-22
references: 20663673
references: Appl Environ Microbiol. 2003 Jun;69(6):3311-6
references: 12788731
references: Arch Mikrobiol. 1973 Nov 19;93(4):367-70
references: 4204950
references: Extremophiles. 2008 Jan;12(1):15-25
references: 17225926
references: Nat Rev Microbiol. 2006 Feb;4(2):113-20
references: 16415927
references: J Bacteriol. 1950 Dec;60(6):771-81
references: 14824070
references: Res Microbiol. 1995 Oct;146(8):697-706
references: 8584792