We report a novel study based on analytical pyrolysis coupled with mass spectrometry to investigate, at the molecular level, the formation of aggregates and cross-linked structures in ovalbumin (OVA). For this scope, OVA was dissolved in water at different concentrations and temperatures (up to 80 °C), and was added with 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide hydrochloride (EDC). The formation of β-sheets and intermolecular aggregates, which are stabilized by weak hydrophobic and hydrogen bonds, is favoured in OVA by higher protein concentration and temperatures. The cross-linker (EDC) gives the formation of covalent bonds randomly distributed in the protein, inducing significant portions of random coil structures in OVA. FTIR-ATR spectroscopy was employed to study the protein conformation. Evolved gas analysis coupled with mass spectrometry (EGA-MS) and pyrolysis coupled with gas chromatography mass spectrometry (Py-GC-MS) were used to characterise the gaseous compounds evolved during pyrolysis at the different temperatures. Aggregation and cross-linking increase the thermal stability of OVA and significantly affect its pyrolytic profile.

The study reveals that analytical pyrolysis coupled to mass spectrometry can be used to gain insights into the protein structure.

我们报告了基于分析热解结合质谱的一项新研究，以在分子水平上研究卵清蛋白（OVA）中聚集体和交联结构的形成。在此范围内，OVA会以不同的浓度和温度（最高80°C）溶于水中，并加入1-乙基-3-（3-二甲基氨基丙基）碳二亚胺盐酸盐（EDC）。通过弱的疏水和氢键稳定的β-折叠和分子间聚集体的形成在OVA中由于较高的蛋白质浓度和温度而受到青睐。交联剂（EDC）形成了随机分布在蛋白质中的共价键，从而在OVA中诱导了随机卷曲结构的重要部分。FTIR-ATR光谱法用于研究蛋白质构象。气相色谱-质谱联用（EGA-MS）和气相色谱-质谱联用（Py-GC-MS）热解用于表征在不同温度下热解过程中产生的气态化合物。聚集和交联增加了OVA的热稳定性，并显着影响了OVA的热解性能。

研究表明，分析热解与质谱联用可用于深入了解蛋白质结构。