title: Pseudomonas cepacia 2,2-dialkylglycine decarboxylase. Sequence and expression in Escherichia coli of structural and repressor genes.
abstract: A 3969-base pair PstI-PstI fragment of Pseudomonas cepacia DNA containing the gene for the pyridoxal 5'-phosphate dependent 2,2-dialkylglycine decarboxylase (pyruvate) (EC 4.1.1.64) was cloned in Escherichia coli. The insert was sequenced by the dideoxy method using nested deletions from both ends, revealing a central 1302-base pair region that codes for the decarboxylase subunit. The recombinant enzyme was expressed in E. coli, purified to homogeneity, and sequenced at the amino terminus. Also, a cofactor-labeled active site peptide was sequenced. The carboxyl terminus of the deduced amino acid sequence is homologous with the carboxyl terminus of mammalian ornithine aminotransferase; the active site sequence is similar to the active site sequences of several other aminotransferases. No homologies with known decarboxylase sequences could be found. Expression of the decarboxylase gene is negatively controlled by a 687-nucleotide sequence upstream of and diverging from the structural gene. Expression is induced by S-isovaline, 2-methylalanine, and D-2-aminobutanoic acid, but not by glycine, D- or L-alanine, L-2-aminobutanoic acid, R-isovaline, or other alkyl amino acids.
authors.affiliation: Department of Chemistry, University of Alaska Fairbanks 99775-0520.
authors.forename: J W
authors.initials: JW
authors.lastname: Keller
authors.forename: K B
authors.initials: KB
authors.lastname: Baurick
authors.forename: G C
authors.initials: GC
authors.lastname: Rutt
authors.forename: M V
authors.initials: MV
authors.lastname: O'Malley
authors.forename: N L
authors.initials: NL
authors.lastname: Sonafrank
authors.forename: R A
authors.initials: RA
authors.lastname: Reynolds
authors.forename: L O
authors.initials: LO
authors.lastname: Ebbesson
authors.forename: F F
authors.initials: FF
authors.lastname: Vajdos
mesh_terms: D000595:Amino Acid Sequence; D001483:Base Sequence; D001665:Binding Sites; D002262:Carboxy-Lyases / Q000235:genetics*; D003001:Cloning, Molecular; D003062:Codon; D004269:DNA, Bacterial / Q000096:biosynthesis / Q000235:genetics; D004926:Escherichia coli / Q000201:enzymology / Q000235:genetics*; D015870:Gene Expression / Q000187:drug effects; D005798:Genes, Bacterial / Q000235:genetics*; D008969:Molecular Sequence Data; D009953:Ornithine-Oxo-Acid Transaminase; D011549:Pseudomonas / Q000201:enzymology* / Q000235:genetics; D011994:Recombinant Proteins; D012689:Sequence Homology, Nucleic Acid
chemical_list: D003062:Codon; D004269:DNA, Bacterial; D011994:Recombinant Proteins; D009953:Ornithine-Oxo-Acid Transaminase; D002262:Carboxy-Lyases; C063519:2,2-dialkylglycine decarboxylase