Conformational substates in azurin.

Protein conformational populations and functionally relevant substates.

Functioning proteins do not remain fixed in a unique structure, but instead they sample a range of conformations facilitated by motions within the protein. Even in the native state, a protein exists as a collection of interconverting conformations driven by thermodynamic fluctuations. Motions on the fast time scale allow a protein to sample conformations in the nearby area of its conformational...

Spectral hole burning and selection of conformational substates in chromoproteins.

We investigated spectral holes burnt at 1.5 K into the origins of several tautomeric forms of mesoporphyrin IX-substituted horseradish peroxidase at pH 8 under pressures up to 2 MPa. From the pressure-induced lineshift the compressibility of the apoprotein could be determined. We found that the compressibility changed significantly when measured at different tautomer origins. It was concluded t...

Molecular dynamics of conformational substates for a simplified protein model

Phosphorylation of an intrinsically disordered segment in Ets1 shifts conformational sampling toward binding-competent substates.

Functions of many proteins are affected by posttranslational modifications of intrinsically disordered (ID) regions, yet little is known about the underlying molecular mechanisms. By combining molecular dynamics simulations and protein docking, we demonstrate that the addition of phosphates to an ID segment adjacent to the PNT domain of Ets1 directs conformational sampling toward substates that...

Revealing conformational substates of lipidated N-Ras protein by pressure modulation.

Regulation of protein function is often linked to a conformational switch triggered by chemical or physical signals. To evaluate such conformational changes and to elucidate the underlying molecular mechanisms of subsequent protein function, experimental identification of conformational substates and characterization of conformational equilibria are mandatory. We apply pressure modulation in co...