In-depth exploration of Hevea brasiliensis latex proteome and "hidden allergens" via combinatorial peptide ligand libraries.

Division of Genetics and Cell Biology, San Raffaele Scientific Institute, 20132 Milano, Italy.
Journal of proteomics (Impact Factor: 5.07). 03/2010; 73(7):1368-80. DOI: 10.1016/j.jprot.2010.03.002
Source: PubMed

ABSTRACT The proteome of Hevea brasiliensis latex has been explored in depth via combinatorial peptide ligand libraries. A total of 300 unique gene products have been identified in this latex, whose proteome has been largely unknown up to the present. In search for unknown allergens, control latex and eluates from the ligand libraries have been fractionated by two-dimensional mapping, blotted and confronted with sera of 18 patients. In addition to the already known and named Hevea major allergens, we have unambiguously detected several others like, for instance: heat shock protein (81 kDa), proteasome subunit (30 kDa), protease inhibitor (8 kDa), hevamine A (43 kDa) and glyceraldehyde-3-phosphate dehydrogenase (37 kDa). Gene Ontology analysis of analyzed fractions has shown that major functions are substantially unchanged after sample treatment, while novel biological functions appeared that were undetectable in the crude sample.

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