13C flux analysis of cyanobacterial metabolism

Abstract

(13)C metabolic flux analysis (MFA) has made important contributions to our understanding of the physiology of model strains of E. coli and yeast, and it has been widely used to guide metabolic engineering efforts in these microorganisms. Recent advancements in (13)C MFA methodology combined with publicly available software tools are creating new opportunities to extend this approach to examine less characterized microbes. In particular, growing interest in the use of cyanobacteria as industrial hosts for photosynthetic production of biofuels and biochemicals has led to a critical need to better understand how cyanobacterial metabolic fluxes are regulated in response to changes in growth conditions or introduction of heterologous pathways. In this contribution, we review several prior studies that have applied isotopic steady-state (13)C MFA to examine heterotrophic or mixotrophic growth of cyanobacteria, as well as recent studies that have pioneered the use of isotopically nonstationary MFA (INST-MFA) to study autotrophic cultures. We also provide recommendations for the design and analysis of INST-MFA experiments in cyanobacteria, based on our previous experience and a series of simulation studies used to assess the selection of measurements and sample time points. We anticipate that this emerging knowledgebase of prior (13)C MFA studies, optimized experimental protocols, and public software tools will catalyze increasing use of (13)C MFA techniques by the cyanobacteria research community.

Metabolic flux analyses of Pseudomonas aeruginosa cystic fibrosis isolates

“…Most MFA studies of microbial systems to date have focused on questions related to biotechnology and metabolic engineering, microbial physiology, and gene function [69][70][71][72][73].…”

Molecular genetic improvements of cyanobacteria to enhance the industrial potential of the microbe: A review

“…However it is important that carbon flux be properly balanced between cell growth and product production . Metabolic flux analysis (MFA) is a mathematical modeling approach used to comprehensively determine the flow of metabolites through intracellular biochemical pathways . A common way to conduct MFA is with C‐labeled substrates .…”

“…99 Metabolic flux analysis (MFA) is a mathematical modeling approach used to comprehensively determine the flow of metabolites through intracellular biochemical pathways. 132 A common way to conduct MFA is with 13 Clabeled substrates. 133 MFA can therefore be used to elucidate targets (such as candidate genes at metabolic bottlenecks) for site-directed mutagenesis to improve metabolic flux.…”

Transcriptional regulator PrqR plays a negative role in glucose metabolism and oxidative stress acclimation in Synechocystis sp. PCC 6803

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