title: Identification and molecular characterization of the aco genes encoding the Pelobacter carbinolicus acetoin dehydrogenase enzyme system.
abstract: Use of oligonucleotide probes, which were deduced from the N-terminal sequences of the purified enzyme components, identified the structural genes for the alpha and beta subunits of E1 (acetoin:2,6-dichlorophenolindophenol oxidoreductase), E2 (dihydrolipoamide acetyltransferase), and E3 (dihydrolipoamide dehydrogenase) of the Pelobacter carbinolicus acetoin dehydrogenase enzyme system, which were designated acoA, acoB, acoC, and acoL, respectively. The nucleotide sequences of acoA (979 bp), acoB (1,014 bp), acoC (1,353 bp), and acoL (1,413 bp) as well as of acoS (933 bp), which encodes a protein with an M(r) of 34,421 exhibiting 64.7% amino acid identity to the Escherichia coli lipA gene product, were determined. These genes are clustered on a 6.1-kbp region. Heterologous expression of acoA, acoB, acoC, acoL, and acoS in E. coli was demonstrated. The amino acid sequences deduced from acoA, acoB, acoC, and acoL for E1 alpha (M(r), 34,854), E1 beta (M(r), 36,184), E2 (M(r), 47,281), and E3 (M(r), 49,394) exhibited striking similarities to the amino acid sequences of the components of the Alcaligenes eutrophus acetoin-cleaving system. Homologies of up to 48.7% amino acid identity to the primary structures of the enzyme components of various 2-oxo acid dehydrogenase complexes also were found. In addition, the respective genes of the 2-oxo acid dehydrogenase complexes and of the acetoin dehydrogenase enzyme system were organized very similarly, indicating a close relationship of the P. carbinolicus acetoin dehydrogenase enzyme system to 2-oxo acid dehydrogenase complexes.
authors.affiliation: Institut für Mikrobiologie der Georg-August-Universität zu Göttingen, Federal Republic of Germany.
authors.forename: F B
authors.initials: FB
authors.lastname: Oppermann
authors.forename: A
authors.initials: A
authors.lastname: Steinbüchel
mesh_terms: D000094:Acetoin Dehydrogenase / Q000096:biosynthesis / Q000235:genetics*; D000123:Acetyltransferases / Q000096:biosynthesis / Q000235:genetics*; D000595:Amino Acid Sequence; D001421:Bacteria, Anaerobic / Q000235:genetics*; D001426:Bacterial Proteins / Q000235:genetics; D001483:Base Sequence; D008058:Dihydrolipoamide Dehydrogenase / Q000096:biosynthesis / Q000235:genetics*; D051047:Dihydrolipoyllysine-Residue Acetyltransferase; D004926:Escherichia coli / Q000235:genetics; D005798:Genes, Bacterial / Q000235:genetics; D008969:Molecular Sequence Data; D009097:Multienzyme Complexes / Q000096:biosynthesis / Q000235:genetics*; D010088:Oxidoreductases / Q000096:biosynthesis / Q000235:genetics*; D011768:Pyruvate Dehydrogenase Complex; D011994:Recombinant Proteins / Q000096:biosynthesis; D012045:Regulatory Sequences, Nucleic Acid / Q000235:genetics; D017422:Sequence Analysis, DNA; D017386:Sequence Homology, Amino Acid; D013466:Sulfurtransferases; D014158:Transcription, Genetic
chemical_list: D001426:Bacterial Proteins; C079999:LipA protein, Bacteria; D009097:Multienzyme Complexes; D011768:Pyruvate Dehydrogenase Complex; D011994:Recombinant Proteins; D010088:Oxidoreductases; D000094:Acetoin Dehydrogenase; C066825:acetoin-2,6-dichlorophenolindophenol oxidoreductase; D008058:Dihydrolipoamide Dehydrogenase; D000123:Acetyltransferases; D051047:Dihydrolipoyllysine-Residue Acetyltransferase; D013466:Sulfurtransferases; C085432:acoS protein, Pelobacter carbinolicus