Stabilization of drug-target proteins by sulfobetaines

2015 Fiscal Year Final Research Report

• Project/Area Number: 24570124
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Structural biochemistry
• Research Institution: Gunma University
• Principal Investigator: Wakamatsu Kaori 群馬大学, 大学院理工学府, 教授 (40222426)
• Co-Investigator(Renkei-kenkyūsha): Terawaki Shin-ichi 群馬大学, 大学院理工学府, 助教 (10452533) ; Iizuka Yasuko 群馬大学, 理工学部, 技術長 (60375566)
• Research Collaborator: Hosoda Kazuo
• Project Period (FY): 2012-04-01 – 2016-03-31
• Keywords: 蛋白質 / 安定化 / スルホベタイン / メカニズム / ダイナミクス / GPCR / Ｇ蛋白質

Outline of Final Research Achievements

Stabilization of proteins (prevention of denaturation and aggregation) is important in drug development. Sulfobetaines are a class of protein stabilizer whose mechanisms remain elusive. To elucidate their stabilizing mechanisms, we analyzed their effects on protein dynamics. We found that NDSB-195 enhances the dynamics of β4-α2 loop of ubiquitin molecules and that NDSB-256 enhances the cis-trans isomerization of an Ala-Pro peptide bond. These effects may contribute the stabilizing activities of sulfobetaines by helping the denatured protein molecules escape from kinetic traps. In addition, by expressing proteins and peptides as fusion proteins, we succeeded in obtaining soluble complex of Gαi1 and its activator peptide designed from the junction between the intracellular third loop and sixth transmembrane helix in the m4 muscarinic acetylcholine receptor. We also identified 3 residues in the peptide that are critical for the binding with Gαi1.

Free Research Field

構造生物学