Pyrophosphate as a central energy carrier in the hydrogen-producing extremely thermophilic Caldicellulosiruptor saccharolyticus

Research output: Contribution to journalArticle


The role of inorganic pyrophosphate (PPi) as an energy carrier in the central metabolism of the extremely thermophilic bacterium Caldicellulosiruptor saccharolyticus was investigated. In agreement with its annotated genome sequence, cell extracts were shown to exhibit PPi-dependent phosphofructokinase and pyruvate phosphate dikinase activity. In addition, membrane-bound pyrophosphatase activity was demonstrated, while no significant cytosolic pyrophosphatase activity was detected. During the exponential growth phase, high PPi levels (approximately 4 +/- 2 mM) and relatively low ATP levels (0.43 +/- 0.07 mM) were found, and the PPi/ATP ratio decreased 13-fold when the cells entered the stationary phase. Pyruvate kinase activity appeared to be allosterically affected by PPi. Altogether, these findings suggest an important role for PPi in the central energy metabolism of C. saccharolyticus.


  • Abraham A. M. Bielen
  • Karin Willquist
  • Jakob Engman
  • John van der Oost
  • Ed van Niel
  • Serve W. M. Kengen
Research areas and keywords

Subject classification (UKÄ) – MANDATORY

  • Industrial Biotechnology
  • Biological Sciences


  • phosphofructokinase, pyrophosphate, H plus -PPase, Caldicellulosiruptor saccharolyticus, glycolysis
Original languageEnglish
Pages (from-to)48-54
JournalFEMS Microbiology Letters
Issue number1
Publication statusPublished - 2010
Publication categoryResearch