These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


Pubmed for Handhelds

PUBMED FOR HANDHELDS

Search MEDLINE/PubMed

  • Title: Chemostat cultivation and transcriptional analyses of Clostridium acetobutylicum mutants with defects in the acid and acetone biosynthetic pathways.
    Author: Hönicke D, Lütke-Eversloh T, Liu Z, Lehmann D, Liebl W, Ehrenreich A.
    Journal: Appl Microbiol Biotechnol; 2014 Dec; 98(23):9777-94. PubMed ID: 25280743.
    Abstract:
    Clostridium acetobutylicum is a model organism for the biotechnologically important acetone-butanol-ethanol (ABE) fermentation. With the objective to rationally develop strains with improved butanol production, detailed insights into the physiological and genetic mechanisms of solvent production are required. Therefore, pH-controlled phosphate-limited chemostat cultivation and DNA microarray technology were employed for an in-depth analysis of knockout mutants with defects in the central fermentative metabolism. The set of studied mutants included strains with inactivated phosphotransacetylase (pta), phosphotransbutyrylase (ptb), and acetoacetate decarboxylase (adc) encoding genes, as well as an adc/pta double knockout mutant. A comprehensive physiological characterization of the mutants was performed by continuous cultivation, allowing for a well-defined separation of acidogenic and solventogenic growth, combined with the advantage of the high reproducibility of steady-state conditions. The ptb-negative strain C. acetobutylicum ptb::int(87) exhibited the most striking metabolite profile: Sizable amounts of butanol (29 ± 1.3 mM) were already produced during acidogenic growth. The product patterns of the mutants as well as accompanying transcriptomic data are presented and discussed.
    [Abstract] [Full Text] [Related] [New Search]