Isolation and characterization of a cysteine protease of freesia corms.
A protease, freesia protease (FP)-A, was purified to electrophoretic homogeneity from regular freesia (Freesia reflacta) corms in harvest time. The Mr of FP-A was estimated to be 24 k by SDS-PAGE. The optimum pH of the enzyme was 8.0 using a casein substrate. These enzymes were strongly inhibited by p-chloromercuribenzoic acid but not by phenylmethane-sulfonylfluoride and EDTA. These results indicate that FP-A belongs to the cysteine proteases. The amino terminal sequence of FP-A was similar to that of papain, and the sequences was regarded to the conservative residues of cysteine protease. From the hydrolysis of peptidyl-p-NAs, the specificity of FP-A was found to be broad. It was thought that FP-A was a new protease from freesia corms.
Uchikoba
Tetsuya
T
Kagoshima University Musium, Japan. uchik@sci.kagoshima-u.ac.jp
Okubo
Michiko
M
Arima
Kazunari
K
Yonezawa
Hiroo
H
D000595:Amino Acid Sequence; D002852:Chromatography, Ion Exchange; D003546:Cysteine Endopeptidases / Q000737:chemistry / Q000302:isolation & purification* / Q000378:metabolism; D004591:Electrophoresis, Polyacrylamide Gel; D007525:Isoelectric Focusing; D019684:Magnoliopsida / Q000201:enzymology*; D008969:Molecular Sequence Data; D017386:Sequence Homology, Amino Acid
D003546:Cysteine Endopeptidases