Serial Millisecond Crystallography of Membrane Proteins

Area of Science:

• Structural Biology
• Biophysics
• X-ray Crystallography

Background:

• Serial femtosecond crystallography (SFX) at X-ray free-electron lasers (XFELs) enables high-resolution structure determination of membrane proteins.
• Synchrotron sources offer more accessible beamtime compared to XFELs.
• Adapting SFX technology to synchrotron sources is crucial for broader application.

Purpose of the Study:

• To adapt serial millisecond crystallography (SMX) for membrane protein structure determination at synchrotron sources.
• To evaluate the compatibility of SMX with de novo phasing methods.
• To explore the potential of SMX for ligand screening and time-resolved studies.

Main Methods:

• Injector-based approach delivering protein crystals in lipidic cubic phase (LCP) or viscous medium.
• Microjet delivery into the unattenuated beam of a synchrotron microfocus beamline.
• Application of serial millisecond crystallography (SMX) techniques.

Main Results:

• Successful application of microjet-based SMX for solving a membrane protein structure.
• Demonstrated compatibility of SMX with de novo phasing.
• Pilot experiments confirm the viability of the SMX approach at synchrotrons.

Conclusions:

• Serial millisecond crystallography (SMX) at synchrotrons is a viable and powerful alternative to SFX for membrane protein structure determination.
• Future developments in synchrotron technology, detectors, and software will enhance SMX capabilities.
• SMX holds significant potential for room-temperature structure determination, ligand screening, and time-resolved studies with minimal radiation damage.