Multiple forms of endopeptidase activity from jojoba seeds.
The cotyledons of 27 day post-germination jojoba seedlings (Simmondsia chinensis) contained five distinct endopeptidase activities separable by DEAE Bio-Gel and CM-cellulose ion exchange chromatography. The endopeptidases were purified 108- to 266-fold and their individuality was confirmed by activity-specific assays in native acrylamide gels along with differences in their Mr and catalytic properties. The five endopeptidases, which showed activity on model substrates and protein, were named EP Ia, EP Ib, EP II, EP III and EP IV. EP Ia was a serine proteinase with a pH optimum of ca 8 and Mr of 58,000. EP Ib, II and III were discrete cysteine proteinases showing pH optima of ca 6.8, 6.0 and 5.4 and Mr of 41,000, 47,000 and 35,000 respectively. EP IV was an aspartic acid proteinase with a ca pH optimum of 3.5 and Mr of 33,000.
Department of Biology, Colorado College, Colorado Springs 80903.
M J
MJ
Wolf
R D
RD
Storey
D010450:Endopeptidases / Q000032:analysis / Q000302:isolation & purification*; D006863:Hydrogen-Ion Concentration; D008970:Molecular Weight; D010944:Plants / Q000201:enzymology*; D011480:Protease Inhibitors / Q000494:pharmacology
D011480:Protease Inhibitors; D010450:Endopeptidases