Small-rotative fixed-target serial synchrotron crystallography (SR-FT-SSX) for molecular crystals

Area of Science:

• Crystallography
• Structural Biology
• Materials Science

Background:

• Ultrabright light sources enable studying smaller crystals faster, but increase X-ray damage risk.
• Serial crystallography (SX) is a multi-crystal method developed to mitigate damage.
• SX is challenging for small unit cell crystals due to limited reflections per image.

Purpose of the Study:

• To present a novel Small-Rotative Fixed-Target Serial Synchrotron Crystallography (SR-FT-SSX) methodology.
• To enable ab initio unit cell determination and atomic-scale structure solution for challenging crystals.
• To overcome limitations of traditional SX for small unit cell crystals.

Main Methods:

• Developed a Small-Rotative Fixed-Target Serial Synchrotron Crystallography (SR-FT-SSX) technique.
• Implemented small-angle rotation of the serial target at each crystal.
• Utilized rigorous quality criteria for selecting partial datasets.

Main Results:

• Achieved high-quality data collection facilitating ab initio unit cell determination.
• Successfully performed atomic-scale structure solution.
• Benchmarked the method using microcrystals of sodium nitroprusside dihydrate.
• Obtained complete data to d_min = 0.6 Å by combining 66 partial datasets.

Conclusions:

• The SR-FT-SSX methodology effectively addresses SX challenges with small unit cell crystals.
• This technique facilitates high-resolution structure determination from limited diffraction data.
• The method shows promise for analyzing small molecules and microcrystals previously inaccessible to SX.