Valutazione della biodiversità in alcuni fruttiferi mediterranei mediante analisi del proteoma.

Proteomic is the study of the overall protein content of a cell, a tissue or an organism, aiming to identification and qualification of all the expressed proteins. Many studies, mainly linked to the development of new medicines or therapies, have so far been focused on the analysis of human proteins. On the other hand, little attention has been given to plant tissues, and in particular to fruit ones. In this study, a proteomic approach was used for the analysis of biodiversity of fruits of some Mediterranean species, and in particular: apple, cv Annurca Rossa del Sud, cv Annurca tradizionale and cv Golden Delicious; peach, cv Percoco di Tunisi; lemon, cv Femminello Siracusano; persimmon, cv Calfuyu; orange, cv Washington Navel; grape, cv Moscato Bianco; prickly pear, cv Gialla. For each sample, the total protein concentration of the saline extract of the pulp was determined, and the protein electrophoretic pattern of the extract was analysed by SDS-PAGE. The fruits under investigation showed a variable protein content, from 20mg/100g of prickly pear to 0.54mg/100g of grape. For each species, a low number of abundant protein, having different molecular weights, was shown. In some cases, a significant variability, dependent on the post-harvesting time, was found. Proteins present in high amounts were analysed by N-terminal amino acid sequencing, and the obtained data were compared to sequences available in Data Banks. The results showed that most of the abundant proteins are involved in mechanisms of plant defence against water and temperature stress, pathogen attack, chemical agents, etc.