Molecular characterization of PadA, a phenylacetaldehyde dehydrogenase from Escherichia coli.
The padA gene encoding the phenylacetaldehyde dehydrogenase involved in the catabolism of 2-phenylethylamine in Escherichia coli has been cloned, sequenced, and located at 31.0 min on the chromosome. The deduced PadA polypeptide contains 499 amino acid residues with a predicted molecular mass of 53.7 kDa, and its primary structure reveals significant similarity with that of members of the aldehyde dehydrogenase superfamily. By engineering optimal transcription and translation elements, a high expression of the padA gene has been achieved. The active PadA enzyme is a homodimer that prefers NAD+ over NADP+ as coenzyme. The enzyme efficiently oxidizes only phenylacetaldehyde-like aromatic aldehydes, and has a weak esterase activity with p-nitrophenol. The padA gene constitutes a new catabolic tool for designing DNA cassettes to expand the abilities of microorganisms to degrade toxic aromatic compounds.
Ferrandez
A
A
Departamento de Microbiologia Molecular, Centro de Investigaciones Biologicas, CSIC, Madrid, Spain.
Prieto
M A
MA
Garcia
J L
JL
Diaz
E
E
D000445:Aldehyde Oxidoreductases / Q000235:genetics*; D000595:Amino Acid Sequence; D001483:Base Sequence; D002874:Chromosome Mapping; D002876:Chromosomes, Bacterial; D003001:Cloning, Molecular; D004274:DNA, Recombinant; D004926:Escherichia coli / Q000201:enzymology*; D029968:Escherichia coli Proteins; D008969:Molecular Sequence Data
D004274:DNA, Recombinant; D029968:Escherichia coli Proteins; D000445:Aldehyde Oxidoreductases; C053855:phenylacetaldehyde dehydrogenase