X-ray photon correlation spectroscopy of protein dynamics at nearly diffraction-limited storage rings

IUCrJ

Madsen, A.¹  Sprung, M.²  Mller, J.³ 

[1] Department Physik, Universitt Siegen, D-57072 Siegen, Germany;Deutsches Elektronen Synchrotron DESY, D-22607 Hamburg, Germany;European X-ray Free Electron Laser Facility, Holzkoppel 4, D-22869 Schenefeld Germany

关键词: MATERIALS SCIENCE;    STRUCTURAL BIOLOGY;    NANOSCIENCE;    RADIATION DAMAGE;    SAXS;    STORAGE RINGS;    X-RAY PHOTON CORRELATION SPECTROSCOPY;    SIGNAL-TO-NOISE RATIO;   

DOI  :  10.1107/S2052252519008273

学科分类：数学（综合）

来源: International Union of Crystallography

【 摘 要 】

This study explores the possibility of measuring the dynamics of proteins in solution using X-ray photon correlation spectroscopy (XPCS) at nearly diffraction-limited storage rings (DLSRs). We calculate the signal-to-noise ratio (SNR) of XPCS experiments from a concentrated lysozyme solution at the length scale of the hydrodynamic radius of the protein molecule. We take into account limitations given by the critical X-ray dose and find expressions for the SNR as a function of beam size, sample-to-detector distance and photon energy. Specifically, we show that the combined increase in coherent flux and coherence lengths at the DLSR PETRA IV yields an increase in SNR of more than one order of magnitude. The resulting SNR values indicate that XPCS experiments of biological macromolecules on nanometre length scales will become feasible with the advent of a new generation of synchrotron sources. Our findings provide valuable input for the design and construction of future XPCS beamlines at DLSRs.

【 授权许可】

CC BY