the co-cultures of C. thermocellum and Thermoanaerobacter pseudethanolicus
39E significantly enhanced ethanol yields from cellulose
fermentation (Ng et al., 1981). A recent study further explored cocultures
consisting of C. thermocellum and various Thermoanaerobacter
strains as the ethanolic fermentative partner, revealing
considerable variations in the ability of the co-cultures to enhance
ethanol production, with the highest ethanol yield observed in the
co-culture of C. thermocellum and Thermoanaerobacter sp. strain
X514 (Fang et al., 2008).
Therefore, the objective of this study was to identify characteristics
contributing to the disparities in the ability of different
Thermoanaerobacter strains to enhance cellulosic bioethanol production
in co-culture with C. thermocellum. Two Thermoanaerobacter
strains, 39E and X514, were compared with physiological and
genomic analysis. Our results show that the presence of the complete
pathway for vitamin B12 biosynthesis is a key determinant
of ethanolic fermentation efficiency in co-cultivation