Purification of five components from Clostridium thermoaceticum which catalyze synthesis of acetate from pyruvate and methyltetrahydrofolate. Properties of phosphotransacetylase.

Crystal structure of a methyltetrahydrofolate- and corrinoid-dependent methyltransferase

“…Initially, MeTr was purified from C. thermoaceticum, where it is expressed as 2% of the total cell protein [23]. The need for large amounts of highly pure MeTr for crystallography was met by subcloning the MeTr gene [24] into the Novagen pET3a protein expression vector and expressing the recombinant enzyme in B834(DE3)pLys5(met -) (Novagen) E. coli cells.…”

“…Here, we report the first crystal structure of an enzyme that catalyzes an MT1 reaction. The C. thermoaceticum MeTr exists as a homodimer of two 28 kDa monomers [23,24]. Its gene has been cloned [25] and actively overexpressed in Escherichia coli [24].…”

Nickel requirement of Acetobacterium woodii

“…Acetobacterium woodii catalyzes the reduction of CO2 to acetate as part of its energy metabolism (1,3,18,20). Evidence has been presented with Clostridium thermoaceticum and Clostridium formicoaceticum that nickel might be involved in this reaction sequence (9,10,13,14). A nickel requirement for growth of the the metal (see below).…”

Levels of enzymes involved in the synthesis of acetate from CO2 in Clostridium thermoautotrophicum

“…The methyl group of methyltetrahydrofolate is probably transferred to a corrinoid enzyme. A recently isolated five-component system from C. thermoaceticum (11) carries out methyl transfer and condensation of this methyl group with carbon monoxide or the C1 of pyruvate (23) to form acetate. Carbon monoxide dehydrogenase, which is present in C. thermoaceticum and C. formicoaceticum (8,10), and a corrinoid enzyme are a part of the five-component system (11).…”