Binding of an Oligomeric Ellagitannin Series to Bovine Serum Albumin (BSA): Analysis by Isothermal Titration Calorimetry (ITC)

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• 作者：Maarit Karonen ; Marianne Oraviita ; Irene Mueller-Harvey ; Juha-Pekka Salminen ; Rebecca J. Green
• 刊名：Journal of Agricultural and Food Chemistry
• 出版年：2015
• 出版时间：December 16, 2015
• 年：2015
• 卷：63
• 期：49
• 页码：10647-10654
• 全文大小：465K
• ISSN：1520-5118

文摘

A unique series of oligomeric ellagitannins was used to study their interactions with bovine serum albumin (BSA) by isothermal titration calorimetry. Oligomeric ellagitannins, ranging from monomer to heptamer and a mixture of octamer鈥搖ndecamers, were isolated as individual pure compounds. This series allowed studying the effects of oligomer size and other structural features. The monomeric to trimeric ellagitannins deviated most from the overall trends. The interactions of ellagitannin oligomers from tetramers to octa鈥搖ndecamers with BSA revealed strong similarities. In contrast to the equilibrium binding constant, enthalpy showed an increasing trend from the dimer to larger oligomers. It is likely that first the macrocyclic part of the ellagitannin binds to the defined binding sites on the protein surface and then the 鈥渇lexible tail鈥?of the ellagitannin coats the protein surface. The results highlight the importance of molecular flexibility to maximize binding between the ellagitannin and protein surfaces.