抗ガン性酵素メチオニンγ-リアーゼに関する研究
スポンサーリンク
概要
- 論文の詳細を見る
Methionine γ-lyase, a pyridoxal-p dependent enzyme which was purified from Pseudomonas putida catalyzes α, γ-elimination and γ-replacement reactions of L-methionine and its derivatives, and also α, β-elimination and β-replacement reactions of S-substitude cysteines. The unique catalytic mechanism of methionine γ-lyase was studied using 1-vinylglycine and the mechanisms of inactivations were studied using suicide substrates, L-propargylglycine, S-(N-methylthiocarbamoyl)-L-cysteine and L-2-amino-4-pantanoate. The enzyme also catalyzes the rapid exchange of the α-and β-hydrogens of methionine and other amino acids with deuterrium from solvents. From these studies, mechanisms for α-and β-hydrogens of the substrate amino acids are initially removed, and then the γ-substitute is eliminated to yield a vinylglycinepyridoxal-P intermediate, which is a common key intermediate in α, γ-elimination and γ- replacement reactions. In addition, the gene encoding this enzyme was cloned and the primary structure of the enzyme was deduced from its nucleotide sequences. The methionine γ-lyase gene was expressed in Escherichia coli. We found a part of an open reading frame (termed mdeB) in the 3'-franking region of the L-methionine γ-lyase gene, suggesting the presence of an operon involved in methionine catabolism. The deduced amino acid sequence of MdeB showed a high homology with the N-terminal region of E1 component of pyruvte dehydrogenase complex from E. coli. We purified and characterized the novel α-ketobutyrate decarboxylase(MdeB) from E. coli transformant. Some of its properties were described.
- 岡山大学農学部の論文
岡山大学農学部 | 論文
- 果物の非破壊品質評価
- 枯損マツに寄生する昆虫群集の羽化
- ホウレンソウ雌性間性株における突然変異誘発ならびに低シュウ酸個体の選抜
- 変化する塩ストレス条件下における湛水の電気伝導度とイネの乾物生産低下の関係
- 塩条件下で発生するイネ（Oryza sativa L.) 高節位分げつの成長とナトリウム蓄積