Isotopically nonstationary 13C metabolic flux analysis guided strain engineering of isobutyraldehyde producing Synechococcus elongatus PCC 7942

Cyanobacterial biotechnologies are paving the way for environmentally conscious and renewable biosynthesis of industrially relevant commodities. These nascent systems, though promising, need to be further optimized in order to achieve yields suitable for industrial applications. Understanding cellular metabolism in industrial conditions is important for strain improvement. We previously developed isotopically nonstationary metabolic flux analysis (INST-MFA) to characterize the photoautotrophic metabolism of Synechocystis PCC 6803 (Young et al. 2011). On-going research in our lab focuses on applying INST-MFA to characterize and predict pathway bottlenecks in engineered cyanobacterial production systems. This presentation will focus on our efforts in applying INST-MFA to an isobutyraldehyde (IBA) producing strain of Synechococcus elongatus PCC 7942 (SA590 (Atsumi et al. 2009)). We also discuss the effect of overexpressing the predicted pathway bottlenecks on cellular metabolism and IBA production. Our goal is to develop INST-MFA as an effective tool for guiding strain engineering of cyanobacterial systems.

References:

1. Young JD, Shastri AA, Stephanopoulos G, Morgan JA (2011) Mapping photoautotrophic metabolism with isotopically nonstationary C-13 flux analysis. Metab Eng 13 (6):656-665. doi:10.1016/j.ymben.2011.08.002

2. Atsumi S, Higashide W, Liao JC (2009) Direct photosynthetic recycling of carbon dioxide to isobutyraldehyde. Nature Biotechnology 27 (12):1177-U1142. doi:10.1038/nbt.1586