Dipartimento di Chimica e Tecnologie Chimiche, Università della Calabria, Rende (CS), Italy.
J Agric Food Chem. 2013 Sep 18;61(37):8949-58. doi: 10.1021/jf4023367. Epub 2013 Sep 4.
Several allergens have been identified and characterized in the genus Citrus, which belongs to the germin-like proteins (GPLs), profilins, and non-specific lipid transfer proteins (nsLTPs). In this work, in silico sequence analysis, protein purification, mass spectrometry identification, and the spectral counting method were integrated to identify new putative allergens of Citrus clementina and their expression level in the fruit peel. The in silico analysis revealed fifteen new sequences belonging to GLPs (Cit cl 1), and two more belonging to nsLTPs (Cit cl 3). No other new sequences were found as regards profilins (Cit cl 2). Each putative allergen from fruit peel was obtained using different protein extraction methods, and the protein sequences of the putative allergens were identified by means of LTQ-Orbitrap XL mass spectrometer. The spectral counting strategy revealed that Cit cl 1 had a higher expression level than Cit cl 2 and Cit cl 3. To predict the quaternary structure and deduced function of Cit cl 1, its primary sequence was used as a template to search a homologous protein structure in the RCSB PDB Database, getting high correspondence with the oxalate oxidase protein in barley.
在芸香科植物中已经鉴定和描述了几种过敏原，它们属于类胚乳蛋白（GPLs）、丝状蛋白和非特异性脂质转移蛋白（nsLTPs）。在这项工作中，我们综合使用了计算机序列分析、蛋白质纯化、质谱鉴定和光谱计数方法，以鉴定新的克莱门氏柑橘潜在过敏原及其在果皮中的表达水平。计算机序列分析揭示了 15 个属于 GLPs（Cit cl 1）的新序列，另外还有 2 个属于 nsLTPs（Cit cl 3）。至于丝状蛋白（Cit cl 2），没有发现其他新序列。使用不同的蛋白质提取方法从果皮中获得每个潜在过敏原，并使用 LTQ-Orbitrap XL 质谱仪鉴定潜在过敏原的蛋白质序列。光谱计数策略表明，Cit cl 1 的表达水平高于 Cit cl 2 和 Cit cl 3。为了预测 Cit cl 1 的四级结构和推导功能，我们使用其一级序列作为模板在 RCSB PDB 数据库中搜索同源蛋白质结构，与大麦中的草酸盐氧化酶蛋白具有高度的一致性。
