Identification of the gene encoding sulfopyruvate decarboxylase, an enzyme involved in biosynthesis of coenzyme M.
The products of two adjacent genes in the chromosome of Methanococcus jannaschii are similar to the amino and carboxyl halves of phosphonopyruvate decarboxylase, the enzyme that catalyzes the second step of fosfomycin biosynthesis in Streptomyces wedmorensis. These two M. jannaschii genes were recombinantly expressed in Escherichia coli, and their gene products were tested for the ability to catalyze the decarboxylation of a series of alpha-ketoacids. Both subunits are required to form an alpha(6)beta(6) dodecamer that specifically catalyzes the decarboxylation of sulfopyruvic acid to sulfoacetaldehyde. This transformation is the fourth step in the biosynthesis of coenzyme M, a crucial cofactor in methanogenesis and aliphatic alkene metabolism. The M. jannaschii sulfopyruvate decarboxylase was found to be inactivated by oxygen and reactivated by reduction with dithionite. The two subunits, designated ComD and ComE, comprise the first enzyme for the biosynthesis of coenzyme M to be described.
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Department of Biochemistry, Virginia Polytechnic Institute and State University, Blacksburg, Virginia 24061-0308, USA.
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D000595:Amino Acid Sequence; D019843:Archaeal Proteins / Q000235:genetics / Q000378:metabolism; D001665:Binding Sites; D002262:Carboxy-Lyases / Q000235:genetics* / Q000378:metabolism; D002384:Catalysis; D004795:Enzyme Stability; D005182:Flavin-Adenine Dinucleotide / Q000378:metabolism; D019766:Genes, Archaeal; D007700:Kinetics; D015080:Mesna / Q000378:metabolism*; D017017:Methanococcus / Q000201:enzymology* / Q000235:genetics; D008969:Molecular Sequence Data; D005810:Multigene Family; D010100:Oxygen; D011767:Pyruvate Decarboxylase / Q000235:genetics* / Q000378:metabolism; D011773:Pyruvates; D019289:Pyruvic Acid; D017386:Sequence Homology, Amino Acid; D013379:Substrate Specificity
D019843:Archaeal Proteins; D011773:Pyruvates; D005182:Flavin-Adenine Dinucleotide; D019289:Pyruvic Acid; D002262:Carboxy-Lyases; C413333:sulfopyruvate decarboxylase, Methanococcus jannaschii; D011767:Pyruvate Decarboxylase; D015080:Mesna; D010100:Oxygen