Effects of mechanical wounding on Carica papaya cysteine endopeptidases accumulation and activity.
The mechanical wounding impact on the Carica papaya latex protein pattern was investigated by analyzing three latexes. A first one commercially available, a second harvested from unripe but fully grown fruits, both obtained from regularly tapped fruits. A third one was collected from similar fruits but wounded for the first time. The results demonstrated both quantitative and qualitative changes in the protein content and in the enzymatic activity. Repeated wounding results in either, accumulation or activation (or both of them) of papain, chymopapain and caricain. Furthermore, new cysteine protease activity was found to transiently accumulate in the latex collected from newly wounded fruits. The possible implication of this enzymatic material in the papaya cysteine endopeptidases pro-forms activation is discussed.
Azarkan
Mohamed
M
University of Brussels, Faculty of Medicine, Protein Chemistry Unit, Campus Erasme CP 609, 808, route de Lennik, B-1070 Brussels, Belgium. mazarkan@ulb.ac.be
Dibiani
Rachid
R
Baulard
Céline
C
Baeyens-Volant
Danielle
D
D029441:Carica / Q000378:metabolism*; D002412:Cations; D002688:Chitinases / Q000737:chemistry; D002845:Chromatography; D002852:Chromatography, Ion Exchange; D010450:Endopeptidases / Q000737:chemistry*; D005638:Fruit; D007840:Latex / Q000378:metabolism; D046911:Macromolecular Substances / Q000737:chemistry; D013053:Spectrophotometry; D013314:Stress, Mechanical
D002412:Cations; D007840:Latex; D046911:Macromolecular Substances; D002688:Chitinases; D010450:Endopeptidases