de.mpg.escidoc.pubman.appbase.FacesBean
English
 
Help Guide Disclaimer Contact us Login
  Advanced SearchBrowse

Item

ITEM ACTIONSEXPORT

Released

Journal Article

Modulation of the Major Paths of Carbon in Photorespiratory Mutants of Synechocystis

MPS-Authors
http://pubman.mpdl.mpg.de/cone/persons/resource/persons97203

Huege,  J.
Applied Metabolome Analysis, Department Willmitzer, Max Planck Institute of Molecular Plant Physiology, Max Planck Society;

http://pubman.mpdl.mpg.de/cone/persons/resource/persons97239

Kopka,  J.
Applied Metabolome Analysis, Department Willmitzer, Max Planck Institute of Molecular Plant Physiology, Max Planck Society;

Locator
There are no locators available
Fulltext (public)
Supplementary Material (public)
There is no public supplementary material available
Citation

Huege, J., Goetze, J., Schwarz, D., Bauwe, H., Hagemann, M., & Kopka, J. (2011). Modulation of the Major Paths of Carbon in Photorespiratory Mutants of Synechocystis. PLoS One, 6(1), e16278. doi:10.1371/journal.pone.0016278.


Cite as: http://hdl.handle.net/11858/00-001M-0000-0014-21BD-1
Abstract
Background: Recent studies using transcript and metabolite profiles of wild-type and gene deletion mutants revealed that photorespiratory pathways are essential for the growth of Synechocystis sp. PCC 6803 under atmospheric conditions. Pool size changes of primary metabolites, such as glycine and glycolate, indicated a link to photorespiration. Methodology/Principal Findings: The C-13 labelling kinetics of primary metabolites were analysed in photoautotrophically grown cultures of Synechocystis sp. PCC 6803 by gas chromatography-mass spectrometry (GC-MS) to demonstrate the link with photorespiration. Cells pre-acclimated to high CO2 (5%, HC) or limited CO2 (0.035%, LC) conditions were pulse-labelled under very high (2% w/w) C-13-NaHCO3 (VHC) conditions followed by treatment with ambient C-12 at HC and LC conditions, respectively. The C-13 enrichment, relative changes in pool size, and C-13 flux of selected metabolites were evaluated. We demonstrate two major paths of CO2 assimilation via Rubisco in Synechocystis, i.e., from 3PGA via PEP to aspartate, malate and citrate or, to a lesser extent, from 3PGA via glucose-6-phosphate to sucrose. The results reveal evidence of carbon channelling from 3PGA to the PEP pool. Furthermore, C-13 labelling of glycolate was observed under conditions thought to suppress photorespiration. Using the glycolate-accumulating Delta glcD1 mutant, we demonstrate enhanced C-13 partitioning into the glycolate pool under conditions favouring photorespiration and enhanced C-13 partitioning into the glycine pool of the glycine-accumulating Delta gcvT mutant. Under LC conditions, the photorespiratory mutants Delta glcD1 and Delta gcvT showed enhanced activity of the additional carbon-fixing PEP carboxylase pathway. Conclusions/Significance: With our approach of non-steady-state C-13 labelling and analysis of metabolite pool sizes with respective C-13 enrichments, we identify the use and modulation of major pathways of carbon assimilation in Synechocystis in the presence of high and low inorganic carbon supplies.