해양생명정보 기반 단백질 엔지리어링을 통한 섬유아세포 성장인자 열안정성 개선

Abstract

FGF2 plays an important role in a wide range of biological functions such as DNA synthesis, cell proliferation, angiogenesis and skin wound healing. This feature makes it attractive as a material for pharmaceuticals and functional cosmetics. However, the short half-life remains a challenge in the development of protein materials. Here, we prepared a thermostable FGF2 mutant protein designed using bioinformatics, molecular thermodynamics and molecular modeling methods and investigated its structural properties through activity and 3D structural elucidation. As a result of protein sequence alignment, only two amino acids (T121S, S137P) were different between human and whale FGF7, and S137P mutation improved thermal stability as proved by SDS-PAGE gel and Circular Dichroism (CD) analysis. The in silico structure of FGF2 revealed that the whale-specific S137P mutant can be stabilized through the π-π interaction with W123, which supported the results for higher thermal stability of S137P mutant. Cysteine ​​protruding from the surface of FGF2 is involved in intermolecular oligomerization of FGF2 proteins, causing protein aggregation. The substitution of Asp28 into Glu reduced protein degradation caused by the addition of GSH or GSSG. The FGF2 D28E/C78I/C96I/S137P mutant exhibited 9.6-fold improved thermal stability (based on 50% residual activity) compared to wild-type FGF2. This study on FGF2 can provide important insights in the development of industrial protein materials.