Location: Renewable Product Technology ResearchTitle: Development of mutated Kluyveromyces marxianus strains for ethanol production at elevated temperature from biomass hydrolysate Author
Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: 5/7/2013
Publication Date: 5/7/2013
Citation: Hughes, S.R., Cox, E.J., Kurtzman, C.P., Bischoff, K.M., Liu, S., Cote, G.L., Rich, J.O., Bang, S.S., Pinkleman, R., Riano-Herrera, N.M., Rodriguez-Valencia, N., Lopez-Nunez, J.C. 2013. Development of mutated Kluyveromyces marxianus strains for ethanol production at elevated temperature from biomass hydrolysate [abstract]. Center for Process Analysis and Control. Interpretive Summary:
Technical Abstract: The yeast K. marxianus has advantages over the most commonly used industrial ethanologen, Saccharomyces cerevisiae, such as the ability to grow at 47°C, to produce ethanol at temperatures above 40°C, and to grow on a wide variety of substrates, including starch, sucrose, pectins, and cellulosic biomass, that make it a promising candidate for development as a versatile, thermotolerant, industrial ethanologen. To improve its growth and ethanol yield at elevated temperature under microaerophilic conditions, wild-type K. marxianus NRRL Y 1109 was irradiated with UV C and the irradiated cultures were selected for growth at elevated temperature using automated protocols on a robotic platform for picking and spreading the cultures and for processing the resulting plates. Two mutant strains were isolated that grew aerobically on glucose at 47°C and anaerobically at 46°C on a wide variety of substrates that are constituents of biomass materials commonly considered feedstocks for renewable fuels. These strains gave higher ethanol yields than wild-type using either glucose (0.51 and 0.43 g ethanol/ g glucose, respectively; P=0.014) or galacturonic acid (0.48 and 0.34 g ethanol/ g galacturonic acid, respectively; P<0.00001) as substrate at 46°C.