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http://purl.uniprot.org/citations/9488680http://www.w3.org/1999/02/22-rdf-syntax-ns#typehttp://purl.uniprot.org/core/Journal_Citation
http://purl.uniprot.org/citations/9488680http://www.w3.org/1999/02/22-rdf-syntax-ns#typehttp://purl.uniprot.org/core/Journal_Citation
http://purl.uniprot.org/citations/9488680http://www.w3.org/2000/01/rdf-schema#comment"Methionine gamma-lyase, the enzyme that catalyzes the breakdown of methionine by an alpha,gamma-elimination reaction and is a member of the gamma-family of pyridoxal 5'-phosphate-dependent enzymes, is present in high activity in the primitive protozoan parasite Trichomonas vaginalis but is absent from mammals. Two genes, mgl1 and mgl2, encoding methionine gamma-lyase, have now been isolated from T. vaginalis. They are both single copy, encode predicted proteins (MGL1 and MGL2) of 43 kDa, have 69% sequence identity with each other, and show a high degree of sequence identity to methionine gamma-lyase from Pseudomonas putida (44%) and other related pyridoxal 5'-phosphate-dependent enzymes such as human cystathionine gamma-lyase (42%) and Escherichia coli cystathionine beta-lyase (30%). mgl1 and mgl2 have been expressed in E. coli as a fusion with a six-histidine tag and the recombinant proteins (rMGL1 and rMGL2) purified by metal-chelate affinity chromatography. rMGL1 and rMGL2 were found to have high activity toward methionine (10.4 and 0.67 mumol/min/mg of protein, respectively), homocysteine (370 and 128 mumol/min/mg of protein), cysteine (6.02 and 1.06 mumol/min/mg of protein), and O-acetylserine (3.74 and 1.51 mumol/min/mg of protein), but to be inactive toward cystathionine. Site-directed mutagenesis of an active site cysteine (C113G for MGL1 and C116G for MGL2) reduced the activity of the recombinant enzymes toward both methionine and homocysteine by approximately 80% (rMGL1) and 90% (rMGL2). In contrast, the activity of mutated rMGL2 toward cysteine and O-acetylserine was increased (to 214 and 142%, respectively), whereas that of mutated rMGL1 was reduced to 39 and 49%, respectively. These findings demonstrate the importance of this cysteine residue in the alpha,beta-elimination and alpha, gamma-elimination reactions catalyzed by trichomonad methionine gamma-lyase."xsd:string
http://purl.uniprot.org/citations/9488680http://purl.org/dc/terms/identifier"doi:10.1074/jbc.273.10.5549"xsd:string
http://purl.uniprot.org/citations/9488680http://purl.org/dc/terms/identifier"doi:10.1074/jbc.273.10.5549"xsd:string
http://purl.uniprot.org/citations/9488680http://purl.uniprot.org/core/author"Coombs G.H."xsd:string
http://purl.uniprot.org/citations/9488680http://purl.uniprot.org/core/author"Coombs G.H."xsd:string
http://purl.uniprot.org/citations/9488680http://purl.uniprot.org/core/author"Mottram J.C."xsd:string
http://purl.uniprot.org/citations/9488680http://purl.uniprot.org/core/author"Mottram J.C."xsd:string
http://purl.uniprot.org/citations/9488680http://purl.uniprot.org/core/author"Walker J."xsd:string
http://purl.uniprot.org/citations/9488680http://purl.uniprot.org/core/author"Walker J."xsd:string
http://purl.uniprot.org/citations/9488680http://purl.uniprot.org/core/author"Edlind T."xsd:string
http://purl.uniprot.org/citations/9488680http://purl.uniprot.org/core/author"Edlind T."xsd:string
http://purl.uniprot.org/citations/9488680http://purl.uniprot.org/core/author"McKie A.E."xsd:string
http://purl.uniprot.org/citations/9488680http://purl.uniprot.org/core/author"McKie A.E."xsd:string
http://purl.uniprot.org/citations/9488680http://purl.uniprot.org/core/date"1998"xsd:gYear
http://purl.uniprot.org/citations/9488680http://purl.uniprot.org/core/date"1998"xsd:gYear
http://purl.uniprot.org/citations/9488680http://purl.uniprot.org/core/name"J. Biol. Chem."xsd:string
http://purl.uniprot.org/citations/9488680http://purl.uniprot.org/core/name"J Biol Chem"xsd:string
http://purl.uniprot.org/citations/9488680http://purl.uniprot.org/core/pages"5549-5556"xsd:string
http://purl.uniprot.org/citations/9488680http://purl.uniprot.org/core/pages"5549-5556"xsd:string
http://purl.uniprot.org/citations/9488680http://purl.uniprot.org/core/title"The primitive protozoon Trichomonas vaginalis contains two methionine gamma-lyase genes that encode members of the gamma-family of pyridoxal 5'-phosphate-dependent enzymes."xsd:string
http://purl.uniprot.org/citations/9488680http://purl.uniprot.org/core/title"The primitive protozoon Trichomonas vaginalis contains two methionine gamma-lyase genes that encode members of the gamma-family of pyridoxal 5'-phosphate-dependent enzymes."xsd:string
http://purl.uniprot.org/citations/9488680http://purl.uniprot.org/core/volume"273"xsd:string
http://purl.uniprot.org/citations/9488680http://purl.uniprot.org/core/volume"273"xsd:string
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