NOVELTY - Isolated polynucleotide (I) comprising a nucleotide sequence encoding an operon that codes for carbon monoxide dehydrogenase, membrane-associated electron transfer protein, ferredoxin oxidoreductase and promoter, where the sequence is at least 77% identical to a fully defined 1881 nucleotides of SEQ ID NO. 1, as given in the specification, is new.    USE - The polynucleotide is useful for producing ethanol (claimed).    DETAILED DESCRIPTION - INDEPENDENT CLAIMS are also included for:    (1) an isolated polynucleotide (II) comprising a nucleotide sequence encoding an operon that codes for acetate kinase, phosphotransacetylase and promoter, where the sequence is at least 76% identical to a fully defined 456 nucleotides of SEQ ID NO 2, as given in the specification;    (2) an isolated polynucleotide (III) comprising a nucleotide sequence encoding a polypeptide that codes for acetyl coenzyme A reductase and promoter, where the sequence is at least 98% identical to a fully defined 1263 nucleotides of SEQ ID NO. 3, as given in the specification;    (3) a vector comprising the polynucleotide (I), (II) or (III);    (4) an isolated transformant containing the polynucleotide (I), (II) or (III);    (5) an isolated transformant carrying the vector;    (6) an anti sense nucleic acid to the nucleotide sequence of the polynucleotide (I), (II) or (III), where the antisense nucleic acid inhibits the expression of the enzyme;    (7) a method of producing ethanol comprising either: isolating and purifying anaerobic, ethanologenic microorganisms carrying the polynucleotide (I) or (II) and fermenting syngas with the microorganisms in a fermentation bioreactor; or isolating and purifying anaerobic, ethanologenic microorganisms carrying the polynucleotide (III), fermenting syngas with the microorganisms in a fermentation bioreactor and providing sufficient growth conditions to facilitate the production of ethanol from acetyl CoA via the reductase;    (8) a method of increasing ethanologenesis in a microorganism containing the nucleotide sequence of the polynucleotide (I), comprising modifying or duplicating a promoter region of the nucleotide sequence to increase the activity of the operon or to cause overexpression of the operon;    (9) a method of increasing ethanologenesis in a microorganism containing the nucleotide sequence of the polynucleotide (II), comprising modifying or downregulating a promoter region of the nucleotide sequence to decrease the activity of the operon or to cause underexpression of the operon; and    (10) a method of increasing ethanologenesis in a microorganism containing the nucleotide sequence of the polynucleotide (III), comprising modifying or duplicating a promoter region of the nucleotide sequence to increase the activity of the acetyl coenzyme A reductase or to cause overexpression of the nucleotide sequence.