Diaminopimelate decarboxylase of Lemna perpusilla: Partial purification and some properties

摘要: Summary Diaminopimelate decarboxylase ( meso -2,6-diaminopimelate carboxy-lyase, EC 4.1.1.20), an enzyme of lysine synthesis, has been extracted from the higher plant Lemna perpusilla grown on a new chemically defined medium. For assay, spectrophotometric method developed which permits direct determination in presence diaminopimelate. The decarboxylase, sulfhydryl enzyme, was partially purified by (NH 4 ) 2 SO fractionation and DEAE-cellulose chromatography. is highly specific for -2,6-diaminopimelate. Pyridoxal 5-phosphate indicated as cofactor. enzymic reaction pH optimum approx. 7.0, temperature coefficient 2.0 (between 15° 40°). substrate affinity [ K m , 0·35 mM) considerably than that corresponding bacterial decarboxylases. These findings support earlier conclusions diaminopimelate-lysine path characteristic evolutionary continuum ranging bacteria to plants.