The occurrence and properties of methenyltetrahydrofolate cyclohydrolase in plants

スポンサーリンク

概要

• 論文の詳細を見る

• Methenyltetrahydrofolate cyclohydrolase (E.C. 3.5.4.9), which is responsible for the enzymatic conversion of 5,10-methenyl-H_4FA to 10-formyl-H_4FA, has been found in various plant tissues. The enzyme was partially purified from pea seedlings and some of its properties were investigated. It was unstable, but was stabilized by the addition of 25% glycerol. The enzyme was purified about 60-fold by fractionation with ammonium sulfate and column chromatography on DEAE-cellulose in the presence of 25% glycerol. Optimum pH for the reaction was 7.7. Michaelis constants for 5,10-methenyl-H_4FA in the forward reaction, and for 10-formyl-H_4FA in the reverse reaction were 4 × 10^<-5> M and 2 × 10^<-4> M, respectively. The apparent equilibrium constant for the reaction was calculated as 50. Enzyme activity was greatly inhibited by the reduced forms of folate derivatives. The probable participation of this enzyme in the regulation of folate coenzyme levels in plant tissues has been suggested.

• 日本植物生理学会の論文

著者

• Iwai Kazuo

  Research Institute For Food Science Kyoto University

• SUZUKI NOBORU

  Research Institute for Food Science, Kyoto University

• Suzuki Noboru

  Research Institute For Food Science Kyoto University

• Suzuki Noboru

  Research Institute For Food Science Kyoto University:(present) Sizuoka Eiwa Junior College

関連論文

• Biosynthesis of folic acid compounds in plants VI. The occurrence and properties of the dihydrofolate-synthesizing enzyme in pea seedlings
• THE DISTRIBUTION OF FROMYLTETRAHYDROFOLATE SYNTHETASE IN PLANTS, AND THE PURIFICATION AND PROPERTIES OF THE ENZYME FROM PEA SEEDLINGS
• The occurrence and properties of methenyltetrahydrofolate cyclohydrolase in plants
• The occurrence and properties of dihydrofolate reductase in pea seedlings

スポンサーリンク