Gołębiowski Adrian, Pomastowski Paweł, Rafińska Katarzyna, Zuvela Petar, Wong Ming Wah, Pryshchepa Oleksandra, Madajski Piotr, Buszewski Bogusław
Centre for Modern Interdisciplinary Technologies, Nicolaus Copernicus University in Torun, 4 Wileńska Street, 87-100 Torun, Poland.
Department of Environmental Chemistry and Bioanalytics, Faculty of Chemistry, Nicolaus Copernicus University in Torun, 7 Gagarina Street, 87-100 Torun, Poland.
ACS Omega. 2022 Oct 21;7(43):38459-38474. doi: 10.1021/acsomega.2c03674. eCollection 2022 Nov 1.
Alpha-lactalbumin (α-LA) and binding of zinc cations to protein were studied. Molecular characteristics of protein was determined by MALDI-TOF/MS and electrophoresis SDS-PAGE, and also, for complexes, it was determined by spectroscopic techniques (ATR-FT-IR and Raman) and microscopic techniques (SEM along with an EDX detector and also TEM). The pH dependence of zeta potential of α-LA was determined in saline solution. The zinc binding to the protein mechanism was investigated; zinc binding to protein kinetics, the molecular modeling by the DFT method, and electron microscopy (SEM and TEM) for microstructure observation were performed. The experiments performed indicate a quick binding process (equilibrium takes place after 2 min of incubation) which occurs onto the surface of α-LA. Zinc cations change the conformation of the protein and create spherical particles from the morphological point of view. DFT studies indicate the participation of acidic functional groups of the protein (aspartic acid and glutamic acid residues), and these have a decisive influence on the interaction with zinc cations. Application studies of general toxicity and cytotoxicity and bioavailability were conducted.
研究了α-乳白蛋白（α-LA）以及锌阳离子与该蛋白质的结合情况。通过基质辅助激光解吸电离飞行时间质谱（MALDI-TOF/MS）和十二烷基硫酸钠聚丙烯酰胺凝胶电泳（SDS-PAGE）测定了蛋白质的分子特征，对于复合物，则通过光谱技术（衰减全反射傅里叶变换红外光谱（ATR-FT-IR）和拉曼光谱）以及显微镜技术（配备能谱仪（EDX）的扫描电子显微镜（SEM）和透射电子显微镜（TEM））进行测定。在盐溶液中测定了α-LA的ζ电位对pH的依赖性。研究了锌与蛋白质的结合机制；进行了锌与蛋白质结合的动力学研究、采用密度泛函理论（DFT）方法的分子建模以及用于微观结构观察的电子显微镜（SEM和TEM）研究。所进行的实验表明，锌与α-LA的结合过程很快（孵育2分钟后达到平衡），且发生在α-LA的表面。从形态学角度来看，锌阳离子改变了蛋白质的构象并形成了球形颗粒。DFT研究表明蛋白质的酸性官能团（天冬氨酸和谷氨酸残基）参与其中，并且这些官能团对与锌阳离子的相互作用具有决定性影响。还开展了一般毒性、细胞毒性及生物利用度的应用研究。
