Tuesday, January 8, 2013

UC Davis team engineers cyanobacterium for enhanced direct production of 2,3-butanediol; design methods for exogenous chemical production

A research team from the University of California, Davis has engineered a 2,3-butanediol (23BD) biosynthetic pathway in the cyanobacterium Synechococcus elongatus PCC7942 to establish design methods for efficient exogenous chemical production in cyanobacteria-a technology area that is still in its infancy compared with model fermentative organisms, they noted.

In a paper published in the Proceedings of the National Academy of Sciences (PNAS), they reported the production by their organism of 23BD from CO2 reached 2.38 g/L-a significant increase for chemical production from exogenous pathways in cyanobacteria. The work demonstrates that developing strong design methods can continue to increase chemical production in cyanobacteria, they suggested.

2,3BD is a key chemical building block used to make polymers, plastics and hydrocarbon fuels; it can be readily converted to intermediaries such as butenes, butadiene and methyl ethyl ketone that are used in the production of hydrocarbon fuels and a variety of chemicals including polymers, synthetic rubbers, plastics and textiles. (Earlier post.)

They selected 23BD as a target chemical with low host toxicity, and designed an oxygen-insensitive, cofactor-matched biosynthetic pathway coupled with irreversible enzymatic steps to create a driving force toward the target.


  • John W. K. Oliver, Iara M.P. Machado, Hisanari Yoneda, and Shota Atsumi (2013) Cyanobacterial conversion of carbon dioxide to 2,3-butanediolPNAS doi: 10.1073/pnas.1213024110

  • Ira M.P. Machado, Shota Atsumi (2012) Cyanobacterial biofuel production, Journal of Biotechnology, Volume 162, Issue 1, Pages 50-56, doi: 10.1016/j.jbiotec.2012.03.005