Tungsten-enhanced growth of Methanosphaera stadtmanae

Bédis Dridi (1) , Saber Khelaifia (1) , Marie Laure Fardeau (2) , Bernard Ollivier (2) , Michel Drancourt (1)

1 URMITE - Unité de Recherche sur les Maladies Infectieuses et Tropicales Emergentes
2 MIO - Institut méditerranéen d'océanologie

Background: The methanogenic Archaea Methanosphaera stadtmanae has been detected in the human gut microbiota by both culture and culture-independent methods. Its growth reaches an exponential phase after 5 to 7-day culture in medium 322 (10% vol). Our recent successful isolation of Methanomassiliicoccus luminyensis, a tungstate-selenite-requiring Archaea sharing similar metabolism characteristics with M. stadtmanae prompted us to study the effects of tungsten and selenium on M. stadtmanae growth. Findings: Addition of 0.2 mg/L sodium tungstate to medium 322 yielded, 48 hours after inoculation, a growth rate equivalent to that obtained after 6 days with control culture as measured by methane monitoring and optical density measurement. Addition of 50 μg/mL sodium selenate had no effect on M. stadtmanae growth. Quantitative real-time PCRs targeting the M. stadtmanae 16S rRNA confirmed these data. Conclusions: These data provide new information regarding the poorly known nutritional requirements of the human gut colonizing organisms M. stadtmanae. Adding sodium tungstate to basal medium may facilitate phenotypic characterization of this organism and additionally aid the isolation of new Archaeafrom complex host microbiota.

Mots clés: Methanogenic Archaea; Methanosphaera stadtmanae; Methanomassiliicoccus luminyensis; Tungsten; Selenium

Domaines: Bactériologie

Bédis Dridi, Saber Khelaifia, Marie Laure Fardeau, Bernard Ollivier, Michel Drancourt. Tungsten-enhanced growth of Methanosphaera stadtmanae. BMC Research Notes, 2012, 5, pp.238. ⟨10.1186/1756-0500-5-238⟩. ⟨hal-00746580⟩