Enhancing Carbon Fixation by Metabolic Engineering: A Model System of Complex Network Modulation Metadata

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  • Main Title Enhancing Carbon Fixation by Metabolic Engineering: A Model System of Complex Network Modulation


  • Author: Stephanopoulos, Dr. Gregory
    Creator Type: Personal


  • Sponsor: United States. Department of Energy.
    Contributor Type: Organization


  • Name: Massachusetts Institute of Technology
    Place of Publication: United States


  • Creation: 2008-04-10


  • English


  • Content Description: In the first two years of this research we focused on the development of a DNA microarray for transcriptional studies in the photosynthetic organism Synechocystis and the elucidation of the metabolic pathway for biopolymer synthesis in this organism. In addition we also advanced the molecular biological tools for metabolic engineering of biopolymer synthesis in Synechocystis and initiated a series of physiological studies for the elucidation of the carbon fixing pathways and basic central carbon metabolism of these organisms. During the last two-year period we focused our attention on the continuation and completion of the last task, namely, the development of tools for basic investigations of the physiology of these cells through, primarily, the determination of their metabolic fluxes. The reason for this decision lies in the importance of fluxes as key indicators of physiology and the high level of information content they carry in terms of identifying rate limiting steps in a metabolic pathway. While flux determination is a well-advanced subject for heterotrophic organisms, for the case of autotrophic bacteria, like Synechocystis, some special challenges had to be overcome. These challenges stem mostly from the fact that if one uses {sup 13}C labeled CO{sub 2} for flux determination, the {sup 13}C label will mark, at steady state, all carbon atoms of all cellular metabolites, thus eliminating the necessary differentiation required for flux determination. This peculiarity of autotrophic organisms makes it imperative to carry out flux determination under transient conditions, something that had not been accomplished before. We are pleased to report that we have solved this problem and we are now able to determine fluxes in photosynthetic organisms from stable isotope labeling experiments followed by measurements of label enrichment in cellular metabolites using Gas Chromatography-Mass Spectrometry. We have conducted extensive simulations to test the method and also are presently validating it experimentally using data generated in collaboration with a research group at Purdue University. As result of these studies we can now determine, for the first time, fluxes in photosynthetic organisms and, eventually, in plants.


  • Keyword: Dna
  • STI Subject Categories: 99 General And Miscellaneous//Mathematics, Computing, And Information Science
  • Keyword: Biological Pathways
  • Keyword: Spectroscopy
  • STI Subject Categories: 59 Basic Biological Sciences
  • Keyword: Synthesis
  • Keyword: Stable Isotopes
  • Keyword: Metabolites
  • Keyword: Transients
  • Keyword: Modulation
  • Keyword: Carbon
  • Keyword: Metabolism
  • Keyword: Physiology
  • Keyword: Bacteria
  • Keyword: Atoms


  • Name: Office of Scientific & Technical Information Technical Reports
    Code: OSTI


  • Name: UNT Libraries Government Documents Department
    Code: UNTGD

Resource Type

  • Report


  • Text


  • Report No.: DOE-FG-99ER15015-Final
  • Grant Number: FG02-99ER15015
  • DOI: 10.2172/928069
  • Office of Scientific & Technical Information Report Number: 928069
  • Archival Resource Key: ark:/67531/metadc902236