Characterization of a syngas-assimilating bacterium Moorella sp. strain Y72

Syngas fermentation has attracted attention as one of the production process for biofuels and commodity chemicals in recent years. Acetogens, a group of anaerobic bacteria, can grow autotrophically on gaseous substrates such as hydrogen and carbon dioxide or syngas and produce acetate via the acetyl-CoA pathway, which is recognized as promising host strain for syngas fermentation process. We have previously reported the isolation of thermophilic acetogen strains, Moorella sp. strain Y72, and transformation with orotate monophosphate decarboxylase gene and kanamycin resistant marker. The transformation efficiency of strains Y72 was 20-fold higher than that of reference strain M. thermoacetica strain ATCC39073. Draft genome sequence analysis suggested that the reason for higher transformation efficiency in Y72 than that in ATCC39073 may be that Y72 possesses only 2 sets of genes considered to be involved in a restriction–modification system, which was half of those found in ATCC39073. It was suggested that Y72 was a suitable host for production material production using a syngas platform. In this study, fermentation performance on different gaseous substrate (carbon monoxide, carbon dioxide and hydrogen) concentration was investigated. Results obtained thus far will be presented and discussed.