title: Genetic analysis of the role of the ABC transporter Ota and Otb in glycine betaine transport in Methanosarcina mazei Gö1.
abstract: The methanogenic archaeon Methanosarcina mazei Gö1 accumulates glycine betaine in response to hypersalinity but differs from most other methanoarchaea in having two gene clusters both encoding a potential glycine betaine transporter, Ota and Otb. We have created mutants with either ota or otb deleted to address their role in salt adaptation. The mutants were not impaired in growth at low or high salt, neither at 37 degrees C nor at lower temperatures. However, the Deltaota mutant was completely defective in glycine betaine transport demonstrating that Ota is the only glycine betaine transporter in M. mazei. The mutation in otb led to increased transcription of ota and thus increased transport and accumulation of glycine betaine suggesting a cross talk between the two transporters.
authors.affiliation: Molecular Microbiology and Bioenergetics, Institute of Molecular Biosciences, Johann Wolfgang Goethe University Frankfurt, Frankfurt am Main, Germany.
authors.forename: Regina
authors.initials: R
authors.lastname: Saum
authors.forename: Ana
authors.initials: A
authors.lastname: Mingote
authors.forename: Helena
authors.initials: H
authors.lastname: Santos
authors.forename: Volker
authors.initials: V
authors.lastname: Müller
mesh_terms: D018528:ATP-Binding Cassette Transporters / Q000235:genetics / Q000378:metabolism*; D019843:Archaeal Proteins / Q000235:genetics / Q000378:metabolism*; D001622:Betaine / Q000378:metabolism*; D002352:Carrier Proteins / Q000235:genetics / Q000378:metabolism*; D003080:Cold Temperature; D019641:DNA, Archaeal / Q000235:genetics; D050485:GABA Plasma Membrane Transport Proteins; D019848:Gene Expression Regulation, Archaeal; D017020:Methanosarcina / Q000235:genetics* / Q000378:metabolism; D005810:Multigene Family; D009154:Mutation; D012965:Sodium Chloride; D014158:Transcription, Genetic; D014170:Transformation, Genetic
chemical_list: D018528:ATP-Binding Cassette Transporters; D019843:Archaeal Proteins; D002352:Carrier Proteins; D019641:DNA, Archaeal; D050485:GABA Plasma Membrane Transport Proteins; C072207:betaine plasma membrane transport proteins; D001622:Betaine; D012965:Sodium Chloride