The invention provides a non-naturally occurring microbial
organism having an acetyl-CoA pathway and the capability of utilizing
syngas or
syngas and
methanol. In one embodiment, the invention provides a non-naturally occurring
microorganism, comprising one or more exogenous proteins conferring to the
microorganism a pathway to convert CO, CO2 and / or H2 to acetyl-
coenzyme A (acetyl-CoA), methyl tetrahydrofolate (methyl-THF) or other desired products, wherein the
microorganism lacks the ability to convert CO or CO2 and H2 to acetyl-CoA or methyl-THF in the absence of the one or more exogenous proteins. For example, the microbial
organism can contain at least one exogenous
nucleic acid encoding an
enzyme or
protein in an acetyl-CoA pathway. The microbial
organism is capable of utilizing synthesis gases comprising CO, CO2 and / or H2, alone or in combination with
methanol, to produce acetyl-CoA. The invention additionally provides a method for producing acetyl-CoA, for example, by culturing an acetyl-CoA producing microbial organism, where the microbial organism expresses at least one exogenous
nucleic acid encoding an acetyl-CoA pathway
enzyme or
protein in a sufficient amount to produce acetyl-CoA, under conditions and for a sufficient period of time to produce acetyl-CoA.