서강대학교

초록 (요약문)

Proteins have evolved to function in various processes in organisms. Among numerous tactics that nature has selected, one effective way to deal with biological processes is the oligomerization of protein to efficiently execute reactions. Thus, constructing artificial protein oligomers can be applied to various biotechnological applications. However, only a few methods have been developed to make protein oligomers and the methods are based on naturally occurring protein-protein interactions, which has limitations in choosing a target and designing the structure. Here, further improving our previous study making protein oligomers with 2,2′-bipyridylalanine (BPA), we developed a new strategy to make a heterodimer and direction-determined oligomers. By incorporating two BPAs in sites where the amino acids are closely located, a single protein could bind to a single metal ion as two BPAs bind to Ni2+ together. Owing to the nature of Ni2+ which forms an octahedral complex with three bipyridine molecules, a protein with a single BPA could bind to the empty coordination site of Ni2+ after the double-BPA protein binds to Ni2+. In this way, we could attach two different maltose-binding protein (MBP) mutants into one complex. Furthermore, by adding another BPA at the opposite side where two BPAs were originally incorporated, we could construct direction-determined protein oligomers. The method we developed can be done with many types of proteins and used in diverse applications including substrate channeling.