Genome-guided analysis of transformation efficiency and carbon dioxide assimilation by Moorella thermoacetica Y72

We determined a draft genome sequence for Moorella thermoacetica strain Y72, a syngas-assimilating bacterium with high transformation efficiency. This strain was confirmed to be M. thermoacetica because its overall genome sequence characteristics were similar to those of M. thermoacetica strain ATCC39073. Y72 was confirmed to carry all the genes encoding the enzymes in the reductive acetyl-CoA pathway, with very high similarities to those of ATCC39073. In addition, it was confirmed to assimilate carbon dioxide using this pathway. However, although both Y72 and ATCC39073 carried common genes encoding several enzymes related to the reductive tricarboxylic acid (TCA) cycle, their gene sets were different. Our results suggested that the reason for higher transformation efficiency in Y72 than that in ATCC39073, a reference strain of M. thermoacetica, 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.