Cyanobacteria Synechococcus sp. PCC 7942 and Synechocystis sp. PCC 6803 show similar changes in the metabolic response to changed CO2 conditions but exhibit significant differences at the transcriptomic level. This study employs a systems biology approach to investigate the difference in metabolic regulation of Synechococcus sp. PCC 7942 and Synechocystis sp. PCC 6803. Presented multi-level kinetic model for Synechocystis sp. PCC 6803 is a new approach integrating and analysing metabolomic, transcriptomic and fluxomics data obtained under high and ambient CO2 levels. Modelling analysis revealed that higher number of different isozymes in Synechocystis 6803 improves homeostatic stability of several metabolites, especially 3PGA by 275%, against changes in gene expression, compared to Synechococcus sp. PCC 7942. Furthermore, both cyanobacteria have the same amount of phosphoglycerate mutases but Synechocystis 6803 exhibits only ~20% differences in their mRNA levels after shifts from high to ambient CO2 level, in comparison to ~500% differences in the case of Synechococcus sp. PCC 7942. These and other data imply that the biochemical control dominates over transcriptional regulation in Synechocystis 6803 to acclimate central carbon metabolism in the environment of variable inorganic carbon availability without extra cost carried by large changes in the proteome.

• MeSH
• metabolismus MeSH
• metabolomika MeSH
• oxid uhličitý metabolismus   MeSH
• regulace genové exprese enzymů * MeSH
• regulace genové exprese u bakterií * MeSH
• stanovení celkové genové exprese MeSH
• Synechococcus genetika   metabolismus   MeSH
• Synechocystis genetika   metabolismus   MeSH
• systémová biologie MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• oxid uhličitý MeSH

Current standard methods for kinetic and genomic modeling cannot provide deep insight into metabolic regulation. Here, we developed and evaluated a multi-scale kinetic modeling approach applicable to any prokaryote. Specifically, we highlight the primary metabolism of the cyanobacterium Synechococcus elongatus PCC 7942. The model bridges metabolic data sets from cells grown at different CO2 conditions by integrating transcriptomic data and isozymes. Identification of the regulatory roles of isozymes allowed the calculation and explanation of the absolute metabolic concentration of 3-phosphoglycerate. To demonstrate that this method can characterize any isozyme, we determined the function of two glycolytic glyceraldehyde-3-phosphate dehydrogenases: one co-regulates high concentrations of the 3-phosphoglycerate, the other shifts the bifurcation point in hexose regulation, and both improve biomass production. Moreover, the regulatory roles of multiple phosphoglycolate phosphatases were defined for varying (non-steady) CO2 conditions, suggesting their protective role against toxic photorespiratory intermediates.

• MeSH
• adenosintrifosfát metabolismus   MeSH
• bakteriální proteiny chemie   fyziologie   MeSH
• glyceraldehyd-3-fosfátdehydrogenasy chemie   fyziologie   MeSH
• homeostáza MeSH
• izoenzymy chemie   fyziologie   MeSH
• kinetika MeSH
• NADP metabolismus   MeSH
• oxid uhličitý MeSH
• oxidace-redukce MeSH
• Synechococcus enzymologie   MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• adenosintrifosfát MeSH
• bakteriální proteiny MeSH
• glyceraldehyd-3-fosfátdehydrogenasy MeSH
• izoenzymy MeSH
• NADP MeSH
• oxid uhličitý MeSH