Wünsch, Daniel and Trautwein, Kathleen and Scheve, Sabine and Hinrichs, Christina and Feenders, Christoph and Blasius, Bernd and Schomburg, Dietmar and Rabus, Ralf (2019) Amino acid and sugar catabolism in the marine bacterium Phaeobacter inhibens DSM 17395 from an energetic viewpoint. Applied and environmental microbiology, 85 (24). e02095-19. ISSN 1098-5336

Full text not available from this repository.

Abstract

Growth energetics and metabolic efficiency contribute to the lifestyle and habitat imprint of microorganisms. Roseobacters constitute one of the most abundant and successful marine bacterioplankton groups. Here, we reflect on the energetics and metabolic efficiency of Phaeobacter inhibens DSM 17395, a versatile heterotrophic roseobacter. Fourteen different substrates (five sugars and nine amino acids) and their degradation pathways were assessed for energetic efficiencies based on catabolic ATP yields, calculated from net formed ATP and reducing equivalents. The latter were converted into ATP by employing the most divergent coupling ratios (i.e., ions per ATP) currently known for F1Fo ATP synthases in heterotrophic bacteria. The catabolic ATP yields of the pathways studied in P. inhibens differed ∼3-fold. The actual free energy costs for ATP synthesis were estimated at 81.6 kJ per mol ATP (3.3 ions per ATP) or 104.2 kJ per mol ATP (4.3 ions per ATP), yielding an average thermodynamic efficiency of ∼37.7% or ∼29.5%, respectively. Growth performance (rates, yields) and carbon assimilation efficiency were determined for P. inhibens growing in process-controlled bioreactors with 10 different single substrates (Glc, Man, N-acetylglucosamine [Nag], Phe, Trp, His, Lys, Thr, Val, or Leu) and with 2 defined substrate mixtures. The efficiencies of carbon assimilation into biomass ranged from ∼28% to 61%, with His/Trp and Thr/Leu yielding the lowest and highest levels. These efficiencies correlated with catabolic and ATP yields only to some extent. Substrate-specific metabolic demands and/or functions, as well as the compositions of the substrate mixtures, apparently affected the energetic costs of growth. These include energetic burdens associated with, e.g., slow growth, stress, and/or the production of tropodithietic acid.

Item Type:	Article
Uncontrolled Keywords:	ATP yieldgrowth energeticsbacterial growth efficiency (BGE)sugarsamino acidssubstrate mixtureRoseobacterPhaeobacter inhibens
Divisions:	Faculty of Mathematics and Science > Institute for Chemistry and Biology of the Marine Environment (ICBM)
Date Deposited:	07 Feb 2020 12:18
Last Modified:	07 Feb 2020 12:18
URI:	https://oops.uni-oldenburg.de/id/eprint/4326
URN:	urn:nbn:de:gbv:715-oops-44075
DOI:	10.1128/AEM.02095-19
Nutzungslizenz:

Actions (login required)

View Item