Vegetable proteomics: the detection of Ole e 1 isoallergens by peptide matching of MALDI MS/MS spectra of underivatized and dansylated glycopeptides.
Ole e 1 (NCBI entry gi|14424429) is the major allergen of Oleaceae family. Multiple isoforms and variants are present in varying degrees of distribution. In this report, we present a new approach to the resolution of multiple forms of Ole e 1 from whole antigen extracts, based on a preliminary chemical fractionation procedure followed by MALDI MS and MS/MS measurements. The characterization of Ole e 1 isoallergens was accomplished through the identification of the amino acid sequence including the glycosylation site and the structure of the glycan moieties. The structure feature of the identified Ole e 1.0102 (gi|2465127), main olive allergen [Olea europaea] (gi|13195753), Major pollen allergen Ole e 1 (gi|33329740) and Ole e 1c (gi|1362131) is represented by the point mutation K(106) --> I and by the presence of a glycan moiety. Two other variants Major pollen allergen (Allergen Ole e1) (Ole e I) (gi|14424429) and Ole e 1.0103 protein [Olea europea] (gi|2465129) were identified as nonglycosylated species. These results, partially in disagreement with Swiss-Prot annotation, were validated by matching the MALDI MS/MS spectra of the natural tryptic mixture with those obtained after deglycosylation.
Napoli
Anna
A
Dipartimento di Chimica, Università della Calabria, Arcavacata di Rende, Italy. amc.napoli@unical.it
Aiello
Donatella
D
Di Donna
Leonardo
L
Moschidis
Petros
P
Sindona
Giovanni
G
D000485:Allergens / Q000032:analysis*; D000595:Amino Acid Sequence; D052179:Antigens, Plant; D006020:Glycopeptides / Q000032:analysis*; D008969:Molecular Sequence Data; D029592:Oleaceae / Q000276:immunology*; D010940:Plant Proteins / Q000032:analysis*; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; D053719:Tandem Mass Spectrometry
D000485:Allergens; D052179:Antigens, Plant; D006020:Glycopeptides; C081946:Ole e I protein, Olea europaea; D010940:Plant Proteins