Journal
PROTEIN JOURNAL
Volume 24, Issue 7-8, Pages 445-453Publisher
SPRINGER
DOI: 10.1007/s10930-005-7640-0
Keywords
Asclepiadeae; cysteine endopeptidase; Philibertia gilliesii; plant latex; plant protease
Categories
Ask authors/readers for more resources
A new papain-like cysteine peptidase isolated from latex of Philibertia gilliesii Hook. et Arn., Apocynaceae (formerly Asclepiadaceae) has been purified and characterized. The enzyme, named philibertain g I, is the most basic component present in latex extracts and was purified by acetone fractionation followed by cation exchange chromatography (SP-Sepharose HR) using FPLC system. Homogeneity was confirmed by SDS-PAGE and mass spectroscopy (MS). Molecular mass of the enzyme was 23,530 Da (MALDI-TOF MS), its isoelectric point was > 10.25, and maximum proteolytic activity (casein) was achieved at pH 7-8. The new protease was inhibited by E-64 a cysteine peptidases inhibitor. K-m was 0.15 mM, using PFLNA as substrate. The N-terminal sequence of philibertain g I (LPASVDWRKEGAVLPIRHQGQCG) was compared with those of twenty plant proteases. Philibertain g I showed the higher degree of identity (73%) with caricain, one of the Carica papaya endopepetidases.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available