Newly discovered Synechococcus sp. PCC 11901 is a robust cyanobacterial strain for high biomass production

Cyanobacteria, which use solar energy to convert carbon dioxide into biomass, are potential solar biorefineries for the sustainable production of chemicals and biofuels. However, yields obtained with current strains are still uncompetitive compared to existing heterotrophic production systems. Here we report the discovery and characterization of a new cyanobacterial strain, Synechococcus sp. PCC 11901, with promising features for green biotechnology. It is naturally transformable, has a short doubling time of approximate to 2hours, grows at high light intensities and in a wide range of salinities and accumulates up to approximate to 33g dry cell weight per litre when cultured in a shake-flask system using a modified growth medium - 1.7 to 3 times more than other strains tested under similar conditions. As a proof of principle, PCC 11901 engineered to produce free fatty acids yielded over 6mM (1.5g L-1), an amount comparable to that achieved by similarly engineered heterotrophic organisms. Wodarczyk et al. discover that cyanobacterium Synechococcus sp. PCC 11901 accumulates three times more biomass than other cyanobacterial strains in the same conditions. An engineered version of this strain also produces as much free fatty acid as other commonly used heterotrophic microorganisms, suggesting its utility for the sustainable production of carbon-based molecules.