Hydration shell differentiates folded and disordered states of a Trp-cage miniprotein, allowing characterization of structural heterogeneity by wide-line NMR measurements.

ABSTRACT: Hydration properties of folded and unfolded/disordered miniproteins were monitored in frozen solutions by wide-line ¹H-NMR. The amount of mobile water as function of T (-80 °C < T < 0 °C) was found characteristically different for folded (TC5b), semi-folded (pH < 3, TCb5(H+)) and disordered (TC5b_N1R) variants. Comparing results of wide-line ¹H-NMR and molecular dynamics simulations we found that both the amount of mobile water surrounding proteins in ice, as well as their thaw profiles differs significantly as function of the compactness and conformational heterogeneity of their structure. We found that (i) at around -50 °C ~50 H₂Os/protein melt (ii) if the protein is well-folded then this amount of mobile water remains quasi-constant up to -20 °C, (iii) i

SUBMITTER: Taricska N 

PROVIDER: S-EPMC6393587 | biostudies-literature | 2019 Feb

REPOSITORIES: biostudies-literature