Saum Regina, Mingote Ana, Santos Helena, Müller Volker
Molecular Microbiology and Bioenergetics, Institute of Molecular Biosciences, Johann Wolfgang Goethe University Frankfurt, Frankfurt am Main, Germany.
Arch Microbiol. 2009 Apr;191(4):291-301. doi: 10.1007/s00203-008-0449-4. Epub 2008 Dec 19.
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.
产甲烷古菌马氏甲烷八叠球菌Gö1在高盐环境下会积累甘氨酸甜菜碱，但与大多数其他甲烷古菌不同的是，它有两个基因簇，都编码一种潜在的甘氨酸甜菜碱转运蛋白，即Ota和Otb。我们构建了ota或otb缺失的突变体，以研究它们在盐适应中的作用。这些突变体在低盐或高盐条件下，无论是在37℃还是更低温度下，生长都没有受到损害。然而，Δota突变体在甘氨酸甜菜碱转运方面完全有缺陷，这表明Ota是马氏甲烷八叠球菌中唯一的甘氨酸甜菜碱转运蛋白。otb的突变导致ota转录增加，从而增加了甘氨酸甜菜碱的转运和积累，这表明两种转运蛋白之间存在相互作用。
