Structural analysis of the L-methionine gamma-lyase gene from Pseudomonas putida

J Biochem. 1995 May;117(5):1120-5. doi: 10.1093/oxfordjournals.jbchem.a124816.


The gene encoding L-methionine gamma-lyase from Pseudomonas putida was cloned and the primary structure of the enzyme was deduced from its nucleotide sequence. The L-methionine gamma-lyase gene was expressed in Escherichia coli. The amino acid sequences of BrCN-digested peptides agreed with the corresponding parts of the L-methionine gamma-lyase sequence determined from the gene structure. The polypeptide is composed of 398 amino acid residues with a calculated molecular weight of 42,626, corresponding to the subunit of the homotetrameric enzyme. The deduced amino acid sequence of L-methionine gamma-lyase only showed extensive homology with other well known alpha,gamma-elimination and/or gamma-replacement pyridoxal 5'-phosphate-dependent enzymes, such as cystathionine gamma-lyase, cystathionine gamma-synthase, and O-acetylhomoserine O-acetylserine sulfhydrylase, that participate in the biosynthesis of sulfur amino acids. However, the deduced essential cysteine residue of L-methionine gamma-lyase was not conserved in these enzymes. We confirmed the presence of a part of an open reading frame in the 3'-flanking region of the L-methionine gamma-lyase gene, which showed high homology with the N-terminal region of pyruvate dehydrogenase (lipoamide) from E. coli, suggesting that it participates in the degradative pathway for L-methionine together with L-methionine gamma-lyase.

MeSH terms

  • Amino Acid Sequence
  • Base Sequence
  • Carbon-Sulfur Lyases / chemistry*
  • Carbon-Sulfur Lyases / genetics*
  • Cloning, Molecular
  • Gene Expression
  • Methionine / metabolism
  • Molecular Sequence Data
  • Open Reading Frames
  • Pseudomonas putida / enzymology*
  • Pseudomonas putida / genetics
  • Pyruvate Dehydrogenase Complex / genetics
  • Sequence Analysis, DNA
  • Sequence Homology, Amino Acid
  • Sequence Homology, Nucleic Acid


  • Pyruvate Dehydrogenase Complex
  • Methionine
  • Carbon-Sulfur Lyases
  • L-methionine gamma-lyase

Associated data

  • GENBANK/D30039