Oxidative and reductive acetyl CoA/carbon monoxide dehydrogenase pathway in Desulfobacterium autotrophicum . 2. Demonstration of the enzymes of the pathway and comparison of CO dehydrogenase

It has been proposed that in some anaerobic facultatively autotrophic bacteria the acetyl CoA/CO dehydrogenase pathway is operating both in the reductive and in the oxidative direction, depending on the growth conditions. One of these anaerobes, the Gram-negative sulfate-reducing eubacterium Desulfobacterium autotrophicum , was examined for enzymes of the proposed pathway. All the required enzyme activities were present in sufficient amounts both in autotrophically and in heterotrophically grown cells, provided that the cellular tetrahydropterin rather than tetrahydrofolate was used as cosubstrate in some of the enzyme assays.