Ethanol metabolic pathway engineering

Metabolic engineering (Section 10.5). Over the last 5 years, metabolic engineering tools have matured to the point that targeted manipulation of C. thermocellum and T. saccharolyticum is possible, although more time and effort are required than would be required for the same manipulations in standard hosts. Near-theoretical ethanol yields and commercially viable titers of produced ethanol have been achieved in T. saccharolyticum. Ethanol yield and titers in C. thermocellum have been substantially increased of late, but are not yet equal to those of T. saccharolyticum. The genes responsible for the PFOR-dependent ethanol production pathway of T. saccharolyticum have recently been characterized, and work to transfer this pathway to C. thermocellum is underway. Available data indicate that ethanol inhibition is metabolic rather than biophysical. 

Thermoanaerobacter saccharolyticum Ethanol Using EMA to design, construct, characterize, and validate an engineered T. saccharolyticum for efficient ethanol production and predict the metabolic pathway evolution of the engineered and evolved mutant. Yes Unrean and Srienc, (2011) and Unrean and Srienc (2012) ... 

Yomano LP, York SW, Ingram LO (1998) Isolation and characterization of ethanol-tolerant mutants of Escherichia coli koll for fuel ethanol production. J Ind Microbiol Biot hnol 20 132-138 Zhang M, Eddy C, Deanda K, Finkestein M, Picataggio S (1995) Metabolic engineering of a pentose metabolism pathway in Ethanologenic Zymomonas-mobilis. Science 267 240-243... 

Lachke A (2002) Biofuel from D-xylose—the second most abundant sugar. Resonance 7(5) 50-58 Li Z, Xiao H, Jiang W, Jiang Y, Yang S (2013) Improvemoit of solvoit production from xylose mother liquor by engineering the xylose metabolic pathway in Clostridium acetobutylicum EA 2018. Appl Biochem Biotechnol 171(3) 555-568. doi 10.1007/sl2010-013-0414-9 Lin Y, Tanaka S (2006) Ethanol fermentation from biomass resources current state and prospects. Appl Microbiol Biotechnol 69(6) 627-642... 

Cooksley, CM., Zhang, Y, Wang, H., Redl, S., Winzer, K., Minton, N.R, 2012. Targeted mutagenesis of the Clostridium acetobutylicum acetone-butanol-ethanol fermentation pathway. Metabolic Engineering 14 (6), 630-641. 

---