Akıllıoğlu H Gül, Çelikbıçak Ömür, Salih Bekir, Gökmen Vural
Food Quality and Safety (FoQuS) Research Group, Department of Food Engineering, Hacettepe University, 06800 Beytepe Campus, Ankara, Turkey.
Department of Chemistry, Hacettepe University, 06800 Beytepe Campus, Ankara, Turkey.
Food Chem. 2017 Feb 15;217:65-73. doi: 10.1016/j.foodchem.2016.08.088. Epub 2016 Aug 26.
In this study electrospray ionization quadrupole time-of-flight (ESI-Q-TOF) mass spectrometry was used to investigate protein glycation. The glycated species of cytochrome C, lysozyme, and β-casein formed during glycation with d-glucose were identified and monitored in binary systems heated at 70°C under dry and aqueous conditions. Cytochrome C had multiple charges in non-glycated state, primarily changing from +13 to +17 positive charges, whereas β-casein had charge states up to +30. Upon heating with glucose at 70°C in aqueous state, attachment of one glucose molecule onto proteins was observed in each charge state. However, heating in dry state caused much more glucose attachment, leading to the formation of multiple glycoforms of proteins. By using ESI-QTOF-MS technique, formation of glycated cytochrome C containing up to 12 glucose moieties were observed, while glycated species containing 6 and 8 glucose moieties were observed for lysozyme and β-casein, respectively in various heating conditions.
在本研究中，采用电喷雾电离四极杆飞行时间（ESI-Q-TOF）质谱法研究蛋白质糖基化。在70°C下干燥和水相条件的二元体系中，对细胞色素C、溶菌酶和β-酪蛋白与d-葡萄糖糖基化过程中形成的糖基化产物进行了鉴定和监测。细胞色素C在非糖基化状态下具有多个电荷，主要从+13个正电荷变为+17个正电荷，而β-酪蛋白的电荷状态高达+30。在水相中于70°C与葡萄糖加热时，在每种电荷状态下均观察到一个葡萄糖分子附着到蛋白质上。然而，在干燥状态下加热导致更多的葡萄糖附着，从而导致蛋白质形成多种糖型。通过使用ESI-QTOF-MS技术，观察到含有多达12个葡萄糖部分的糖基化细胞色素C的形成，而在各种加热条件下，分别观察到溶菌酶和β-酪蛋白含有6个和8个葡萄糖部分的糖基化产物。
