Folding and binding of an intrinsically disordered protein: Fast, but not 'diffusion-limited'
Publikation: Bidrag til tidsskrift › Tidsskriftartikel › Forskning › fagfællebedømt
Coupled folding and binding of intrinsically disordered proteins (IDPs) is prevalent in biology. As the first step toward understanding the mechanism of binding, it is important to know if a reaction is 'diffusion-limited' as, if this speed limit is reached, the association must proceed through an induced fit mechanism. Here, we use a model system where the 'BH3 region' of PUMA, an IDP, forms a single, contiguous α-helix upon binding the folded protein Mcl-1. Using stopped-flow techniques, we systematically compare the rate constant for association (k+) under a number of solvent conditions and temperatures. We show that our system is not 'diffusion-limited', despite having a k+ in the often-quoted 'diffusion-limited' regime (10 5-106 M-1 s-1 at high ionic strength) and displaying an inverse dependence on solvent viscosity. These standard tests, developed for folded protein-protein interactions, are not appropriate for reactions where one protein is disordered.
Originalsprog | Engelsk |
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Tidsskrift | Journal of the American Chemical Society |
Vol/bind | 135 |
Udgave nummer | 4 |
Sider (fra-til) | 1415-1422 |
Antal sider | 8 |
ISSN | 0002-7863 |
DOI | |
Status | Udgivet - 30 jan. 2013 |
Eksternt udgivet | Ja |
ID: 244651199