This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Email this article to a friend Similar articles in this journal Similar articles in Web of Science Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via CrossRef Citing Articles via Web of Science (15) Citing Articles via Google Scholar Google Scholar Articles by Yamaoka, Y. Articles by Morohashi, Y. Search for Related Content PubMed PubMed Citation Articles by Yamaoka, Y. Articles by Morohashi, Y. Agricola Articles by Yamaoka, Y. Articles by Morohashi, Y.

Metabolism and Enzymology

Purification and Characterization of a Cysteine Endopeptidase in Cotyledons of Germinated Mung Bean Seeds ¹

Faculty of Agriculture, Tokyo University of Agriculture and Technology, Fuchu, Tokyo 183, Japan

A cysteine endopeptidase (EC 3.4.22.-) present in cotyledons of mung bean (Vigna radiata) seedlings was purified to homogeneity, as judged by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE). This proteinase has an apparent molecular mass of 33 kilodaltons as estimated by SDS-PAGE and belongs to the class of cysteine proteinases as judged by the effects of various proteinase inhibitors on the activity of the enzyme. When proangiotensin is used as a substrate, the enzyme preferentially hydrolyzes the peptide bonds formed by the amino group of Leu or lle in this oligopeptide chain; for the enzyme to cleave those bonds, peptide sequences consisting of at least three amino acid residues on the amino side of Leu or lle must be present. The proteinase readily digests globulin present in mung bean cotyledons to smaller polypeptides.