Metabolic Engineering of Thermoanaerobacterium thermosaccharolyticum for Increased n-Butanol Production

Ashwini Bhandiwad, Anna Guseva, Lee Lynd

Dartmouth College, Hanover, USA.
Mascoma Corporation, Lebanon, USA.

DOI: 10.4236/aim.2013.31007                

Abstract

Thermoanaerobacterium thermosaccharolyticum shows promise as a host for n-butanol production since it natively has the required genes involved in the n-butanol biosynthetic pathway. Overexpression of the natively occurring bcs operon containing the genes thl, hbd, crt, bcd, etfA, and etfB responsible for the formation of butyryl CoA increased the n-butanol production by 180% compared to the wild type from a n-butanol titer of 1.8 mM to 5.1 mM. The deletion of one of the six alcohol dehydrogenase genes confirmed that it was the primary gene responsible for ethanol and n-butanol production from acetyl CoA and butyryl CoA respectively.

Keywords

Biofuels; n-Butanol; Thermophile; Metabolic Engineering

Conflicts of Interest

The authors declare no conflicts of interest.

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