Allergenic proteins detection

Proteins were then dissolved in 20 mL of 0.125 M Tris-HCl, pH 7.4 containing 1% (m/v) CHAPS and the protease inhibitor cocktail, and treated with CPLL. With several variations from the standard treatments such as other complementary extractions from seeds, the use of urea-containing extraction buffer, and an additional peptide ligand library, the total number of detected gene products was quite large. Two hundred and thirty one unique proteins were found in the pulp (vs. 56 described previously) and 61 in the seeds (vs. only four reported by the literature). In the latter case, the presence of seed storage proteins, oleosins, and histones were detected in the pulp, a thaumatin-like protein, an allergenic protein also named Ole el3, was confirmed. 

Other applications involve detection of adulteration of dairy products with soy, pea, and wheat proteins (Haasnoot et al., 2001), presence of asrcasein in milk (the detection threshold for this protein was 0.87pg/mL) (Muller-Renaud et al., 2005), [3-casein in milk and cheese (Muller-Renard et al., 2004), and detection of peanut allergenic proteins (the detection threshold for this protein was 0.7 pg/mL) (Mohammed et al., 2001). 

Soeria-Atmadja, D., Lundell, T., Gustafsson M. G., and Hammerling U. 2006. Computational detection of allergenic proteins attains a new level of accuracy with in silico variable-length peptide extraction and machine learning. Nucleic Acids Res 34(13) 3779-3793. 

Because allergenic food proteins are responsible for the sensitization and elicitation of allergic reactions, most detection methods have been based on the detection of these proteins. Alternatively, DNA has been suggested as a target for the detection of allergenic material in food. However, its use has been a controversial topic because the correlation between the presence of allergenic protein and DNA in processed food may not be constant. At least four factors may affect this correlation ... 

Westphal CD, Pereira MR, Rayboume RB, Williams KM (2004). Evaluation of extraction buffers using the current approach of detecting multiple allergenic and non-allergenic proteins in food. J. AOAC Int., 87(6) 1458-1465. 

The main goal of the tests for soy detection is to verify the absence of soy as a species regardless of the target molecules that will be analyzed. As written above, allergenic proteins are not well characterized yet, and in some cases their concentration is too low to be detected. For these reasons, analytical methods could target other than allergenic proteins or molecules different from proteins (e.g., DNA). 

Shim Y, Wanasundara JPD (2008). Quantitative detection of allergenic protein Sinai from yellow mustard (Sinapis alba L.) seeds using enzyme-linked immunosorbent assay. J. Agric. Food Chemi, 56 1184—1192. 

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