Determination of absolute intramolecular distances in proteins using anomalous X-ray scattering interferometry.

ABSTRACT: Biomolecular structures are typically determined using frozen or crystalline samples. Measurement of intramolecular distances in solution can provide additional insights into conformational heterogeneity and dynamics of biological macromolecules and their complexes. The established molecular ruler techniques used for this (NMR, FRET, and EPR) are, however, limited in their dynamic range and require model assumptions to determine absolute distance or distance distributions. Here, we introduce anomalous X-ray scattering interferometry (AXSI) for intramolecular distance measurements in proteins, which are labeled at two sites with small gold nanoparticles of 0.7 nm radius. We apply AXSI to two different cysteine-variants of maltose binding protein in the presence and absence of its ligand mal

SUBMITTER: Stubhan S 

PROVIDER: S-EPMC11653172 | biostudies-literature | 2025 Feb

REPOSITORIES: biostudies-literature