2KDM

NMR structures of GA95 and GB95, two designed proteins with 95% sequence identity but different folds and functions

2KDM の概要

• エントリーDOI: 10.2210/pdb2kdm/pdb
• NMR情報: BMRB: 16117
• 分子名称: DESIGNED PROTEIN (1 entity in total)
• 機能のキーワード: evolution, folding, protein design, igg binding protein
• タンパク質・核酸の鎖数: 1
• 化学式量合計: 6363.28

構造登録者

He, Y.,Alexander, P.,Chen, Y.,Bryan, P.,Orban, J. (登録日: 2009-01-12, 公開日: 2009-12-29, 最終更新日: 2024-05-22)

主引用文献

Alexander, P.A.,He, Y.,Chen, Y.,Orban, J.,Bryan, P.N.
From the Cover: A minimal sequence code for switching protein structure and function.
Proc.Natl.Acad.Sci.USA, 106:21149-21154, 2009

PubMed Abstract: We present here a structural and mechanistic description of how a protein changes its fold and function, mutation by mutation. Our approach was to create 2 proteins that (i) are stably folded into 2 different folds, (ii) have 2 different functions, and (iii) are very similar in sequence. In this simplified sequence space we explore the mutational path from one fold to another. We show that an IgG-binding, 4beta+alpha fold can be transformed into an albumin-binding, 3-alpha fold via a mutational pathway in which neither function nor native structure is completely lost. The stabilities of all mutants along the pathway are evaluated, key high-resolution structures are determined by NMR, and an explanation of the switching mechanism is provided. We show that the conformational switch from 4beta+alpha to 3-alpha structure can occur via a single amino acid substitution. On one side of the switch point, the 4beta+alpha fold is >90% populated (pH 7.2, 20 degrees C). A single mutation switches the conformation to the 3-alpha fold, which is >90% populated (pH 7.2, 20 degrees C). We further show that a bifunctional protein exists at the switch point with affinity for both IgG and albumin.

PubMed: 19923431
DOI: 10.1073/pnas.0906408106

実験手法

SOLUTION NMR