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Title: Glycogen Synthesis and Metabolite Overflow Contribute to Energy Balancing in Cyanobacteria

Understanding how living cells manage high-energy metabolites such as ATP and NADPH is essential for understanding energy transformations in the biosphere. Using light as the energy input, we find that energy charge (ratio of ATP over ADP+ATP) in the cyanobacterium Synechocystis sp. PCC 6803 varies in different growth stages, with a peak upon entry into the rapid growth phase, as well as a positive correlation with light intensity. In contrast, a mutant that can no longer synthesize the main carbon storage compound glycogen showed higher energy charge. The overflow of organic acids in this mutant under nitrogen depletion could also be triggered under high light in nitrogen-replete conditions, with an energy input level dependency. Lastly, these findings suggest that energy charge in cyanobacteria is tightly linked to growth and carbon partition and that energy management is of key significance for their application as photosynthetic carbon dioxide-assimilating cell factories.
 [1] ;  [2] ;  [2] ;  [2] ;  [1] ;  [3] ;  [1]
  1. National Renewable Energy Lab. (NREL), Golden, CO (United States)
  2. Oklahoma State Univ., Stillwater, OK (United States)
  3. Purdue Univ., West Lafayette, IN (United States)
Publication Date:
Report Number(s):
Journal ID: ISSN 2211-1247
Grant/Contract Number:
AC36-08GO28308; FG02-08ER15968; SC0008628
Published Article
Journal Name:
Cell Reports
Additional Journal Information:
Journal Volume: 23; Journal Issue: 3; Journal ID: ISSN 2211-1247
Research Org:
National Renewable Energy Lab. (NREL), Golden, CO (United States)
Sponsoring Org:
USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22)
Country of Publication:
United States
09 BIOMASS FUELS; cyanobacteria; synechocystis; energy charge; glycogen; overflow metabolism; photosynthesis
OSTI Identifier:
Alternate Identifier(s):
OSTI ID: 1435697