Broadband Dynamics of Ubiquitin by Anionic and Cationic Nanoparticle-Assisted NMR Spin Relaxation.
Broadband Dynamics of Ubiquitin by Anionic and Cationic Nanoparticle-Assisted NMR Spin Relaxation.
Angew Chem Int Ed Engl. 2020 Sep 09;:
Authors: Wardenfelt S, Xiang X, Xie M, Yu L, Bruschweiler-Li L, Bruschweiler R
Abstract
The quantitative and comprehensive description of the internal dynamics of proteins is critical for understanding their function. Nanoparticle-assisted 15 N NMR spin relaxation is a new method that uses a simple read-out allowing the observation of ps - ?s dynamics of proteins when transiently interacting with the surface of nanoparticles. The method is applied here to the widely studied protein human ubiquitin in the presence of anionic and cationic silica nanoparticles (SNP) of different size. The resulting backbone dynamics profiles are highly reproducible and strikingly similar to each other, indicating that, with the exception of the disordered tail, specific protein-SNP interactions are unimportant. The dynamics profiles closely match the sub-ns dynamics S 2 values observed by model-free analysis of standard 15 N relaxation of ubiquitin in free solution. These results indicate that the bulk of ubiquitin backbone dynamics in solution is confined to sub-ns timescales and, hence, it is dynamically considerably more restrained than some previous NMR studies have suggested.
PMID: 32909358 [PubMed - as supplied by publisher]
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