Cultivation of the first mesophilic representative ("mesotoga") within the order Thermotogales

Wajdi Ben Hania (1) , Ramzi Ghodbane (1) , Anne Postec (1) , Celine Brochier-Armanet (2) , Moktar Hamdi (3) , Marie Laure Fardeau (1) , Bernard Ollivier (1)

1 Laboratoire de Microbiologie et Biotechnologie des Environnements Chauds
2 LCB - Laboratoire de chimie bactérienne
3 INSAT - Institut National des Sciences Appliquées et de Technologie [Tunis]

Cultivated members of the order Thermotogales comprise only thermophilic to hyperthermophilic anaerobic microorganisms. However, based on molecular studies, the existence of mesophilic members ("mesotoga") within this order has been postulated but has not been demonstrated by cultural approaches so far. A "mesotoga" (strain PhosAc3) that belonged to an uncultivated lineage distantly related to the thermophilic Kosmotoga genus has now been cultivated in axenic culture. It grew between 30 degrees C and 50 degrees C (optimum 40 degrees C) and oxidized lactate using elemental sulphur as a terminal electron acceptor. Further genomic and physiological characterization of strain PhosAc3 will be important not only for understanding bacterial adaptation to high and moderate temperatures at small evolutionary scales, but also because "mesotoga" might play a crucial ecological role in ecosystems polluted by aromatic compounds. (C) 2011 Elsevier GmbH. All rights reserved.

Mots clés: SP. NOV; Anaerobic bacterium; Evolution; Mesophilic; "Mesotoga"; Phylogeny; Thermotogales; Strain PhosAc3; "Mesotoga sulfurreducens"; THERMOPHILIC BACTERIUM; MICROBIAL COMMUNITY; SP. NOV.; ANCESTOR; CULTURES; SULFATE; WATER; Mesotoga; Mesotoga sulfurreducens

Domaines: Systématique, phylogénie et taxonomie

Wajdi Ben Hania, Ramzi Ghodbane, Anne Postec, Celine Brochier-Armanet, Moktar Hamdi, et al.. Cultivation of the first mesophilic representative ("mesotoga") within the order Thermotogales. Systematic and Applied Microbiology, 2011, 34, pp.581-585. ⟨10.1016/j.syapm.2011.04.001⟩. ⟨hal-00748961⟩