Print Email Facebook Twitter Molecular and physiological adaptations to low temperature in thioalkalivibrio strains isolated from soda lakes with different temperature regimes Title Molecular and physiological adaptations to low temperature in thioalkalivibrio strains isolated from soda lakes with different temperature regimes Author Ahn, Anne Catherine (Universiteit van Amsterdam) Jongepier, Evelien (Universiteit van Amsterdam) Merijn Schuurmans, J. (Universiteit van Amsterdam) Irene, W. (NIOZ Royal Netherlands Institute for Sea Research) Sinninghe Damsté, Jaap S. (NIOZ Royal Netherlands Institute for Sea Research; Universiteit Utrecht) Galinski, Erwin A. (Rheinische Friedrich-Wilhelms University, Bonn) Roman, Pawel (Wetsus, European Centre of Excellence for Sustainable Water Technology) Sorokin, Dimitry Y. (TU Delft BT/Environmental Biotechnology; Russian Academy of Sciences) Muyzer, Gerard (Universiteit van Amsterdam) Date 2021 Abstract The genus Thioalkalivibrio comprises sulfur-oxidizing bacteria thriving in soda lakes at high pH and salinity. Depending on the geographical location and the season, these lakes can strongly vary in temperature. To obtain a comprehensive understanding of the molecular and physiological adaptations to low temperature, we compared the responses of two Thioalkalivibrio strains to low (10 C) and high (30 C) temperatures. For this, the strains were grown under controlled conditions in chemostats and analyzed for their gene expression (RNA sequencing [RNA-Seq]), membrane lipid composition, and glycine betaine content. The strain Thioalkalivibrio versutus AL2T originated from a soda lake in southeast Siberia that is exposed to strong seasonal temperature differences, including freezing winters, whereas Thioalkalivibrio nitratis ALJ2 was isolated from an East African Rift Valley soda lake with a constant warm temperature the year round. The strain AL2T grew faster than ALJ2 at 10 C, likely due to its 3-fold-higher concentration of the osmolyte glycine betaine. Moreover, significant changes in the membrane lipid composition were observed for both strains, leading to an increase in their unsaturated fatty acid content via the Fab pathway to avoid membrane stiffness. Genes for the transcriptional and translational machinery, as well as for counteracting cold-induced hampering of nucleotides and proteins, were upregulated. Oxidative stress was reduced by induction of vitamin B12 biosynthesis genes, and growth at 10 C provoked downregulation of genes involved in the second half of the sulfur oxidation pathway. Genes for intracellular signal transduction were differentially expressed, and interestingly, AL2T upregulated flagellin expression, whereas ALJ2 downregulated it. Subject Glycine betaineMembrane lipid compositionRNA-SeqSoda lakeSystem biologyThioalkalivibrio To reference this document use: http://resolver.tudelft.nl/uuid:c78664ea-6cf0-4458-b24c-e177f9cd0891 DOI https://doi.org/10.1128/MSYSTEMS.01202-20 Source mSystems, 6 (2) Part of collection Institutional Repository Document type journal article Rights © 2021 Anne Catherine Ahn, Evelien Jongepier, J. Merijn Schuurmans, W. Irene, Jaap S. Sinninghe Damsté, Erwin A. Galinski, Pawel Roman, Dimitry Y. Sorokin, Gerard Muyzer Files PDF mSystems.01202_20.pdf 1.48 MB Close viewer /islandora/object/uuid:c78664ea-6cf0-4458-b24c-e177f9cd0891/datastream/OBJ/view