Fig. 5: Phosphomimetic mutations lead to an unlocking of the MD.

A Hsp26 (20 µg) was crosslinked by the addition of 2.7 mM DSG for 1 h at 25 °C. MS measurements were performed on a Thermo Fusion mass spectrometer and the data evaluated in Kojak and visualized with Proxl. The crosslinks are indicated by lines connecting the respective residues. The thickness and color of the lines correspond to the number of peptide spectrum matches (light gray: PSMS = 1–black: PSMS = 5). Dashed lines represent loop-links. White lines in the schematic sequence representation indicate possible crosslink positions. The beige bar represents the sequence coverage. All proteins were measured in triplicates, whereas only one exemplary replicate is shown. B Two views of the pseudo-atomic model with the ribbon colored as in Fig. 1A. Potential phosphorylation sites in the stick and ball representation are colored magenta and lysine residues involved in crosslinking as stick model are colored black. C Measured intra-dimer crosslinks were mapped on one exemplary dimer and shown as black dashed lines. Distances between the Cα atoms were measured in Chimera and are indicated the pictures. D Measured inter-dimer crosslinks are indicated by black dashed lines in the structure segment. Distances between the Cα atoms were measured in Chimera and are indicated in the pictures.