title: Analyses of soluble and membrane proteomes of Ralstonia eutropha H16 reveal major changes in the protein complement in adaptation to lithoautotrophy.
abstract: The soil-dwelling lithoautotrophic bacterium Ralstonia eutropha H16 utilizes hydrogen as the key source of energy during aerobic growth on hydrogen and carbon dioxide. We examined the soluble and membrane protein complements of lithoautotrophically grown cells and compared them to the protein complements of cells grown organoheterotrophically on succinate. (14)N/(15)N-based inverse metabolic labeling in combination with GeLC-MS led to the identification of 1452 proteins, 1174 of which could be quantitated. Far more proteins were found to be more abundant in the lithoautotrophically than in the organoheterotrophically grown cells. In addition to the induction of the key enzymes of hydrogen oxidation and carbon dioxide fixation, we observed several characteristic alterations in the proteome correlated with lithoautotrophic growth. (I) Genes for three terminal oxidases were upregulated. (II) NAD(P) transhydrogenase and enzymes for the accumulation of poly(3-hydroxybutyrate) (PHB) showed increased protein abundance. (III) Lithoautotrophically grown cells were equipped with an enhanced inventory of transport systems. (IV) The expression of cell surface appendages involved in cell movement was markedly increased, while proteins involved in cell adhesion were decreased. Our data show that the hydrogen-based lifestyle of R. eutropha H16 relies on an extensive protein repertoire adapting the organism to the alternative energy and carbon sources.
authors.affiliation: Institut für Biologie, Humboldt-Universität zu Berlin, 10115 Berlin, Germany.
authors.forename: Yvonne
authors.initials: Y
authors.lastname: Kohlmann
authors.forename: Anne
authors.initials: A
authors.lastname: Pohlmann
authors.forename: Andreas
authors.initials: A
authors.lastname: Otto
authors.forename: Dörte
authors.initials: D
authors.lastname: Becher
authors.forename: Rainer
authors.initials: R
authors.lastname: Cramm
authors.forename: Steffen
authors.initials: S
authors.lastname: Lütte
authors.forename: Edward
authors.initials: E
authors.lastname: Schwartz
authors.forename: Michael
authors.initials: M
authors.lastname: Hecker
authors.forename: Bärbel
authors.initials: B
authors.lastname: Friedrich
mesh_terms: D000222:Adaptation, Physiological; D001426:Bacterial Proteins / Q000378:metabolism*; D002245:Carbon Dioxide / Q000378:metabolism; D002352:Carrier Proteins / Q000378:metabolism; D003470:Culture Media; D020118:Cupriavidus necator / Q000254:growth & development / Q000378:metabolism / Q000502:physiology*; D004579:Electron Transport / Q000502:physiology; D020869:Gene Expression Profiling; D006859:Hydrogen / Q000378:metabolism; D008565:Membrane Proteins / Q000378:metabolism*; D020409:Molecular Motor Proteins / Q000378:metabolism; D009249:NADP / Q000378:metabolism; D020543:Proteome / Q000378:metabolism*; D012808:Sigma Factor / Q000378:metabolism; D019802:Succinic Acid; D053719:Tandem Mass Spectrometry
chemical_list: D001426:Bacterial Proteins; D002352:Carrier Proteins; D003470:Culture Media; D008565:Membrane Proteins; D020409:Molecular Motor Proteins; D020543:Proteome; D012808:Sigma Factor; D002245:Carbon Dioxide; D009249:NADP; D006859:Hydrogen; D019802:Succinic Acid