A minimal view of single-particle imaging with X-ray lasers

• Published in: Philosophical transactions of the Royal Society of London. Series B. Biological sciences Vol. 369; no. 1647; p. 20130328
• Main Author: Loh, N. Duane
• Format: Journal Article
• Language: English
• Published: England The Royal Society 17.07.2014
• Subjects: Algorithms; Bioimaging; Coherent Diffraction; Electrons; Lasers; Models, Theoretical; Molecular Conformation; Part II: Technique development; Review; Single Particle Imaging; Time Factors; X-Ray Diffraction - methods; X-Ray Free-Electron Laser; single particle imaging; X-ray free-electron laser; coherent diffraction; bioimaging
• ISSN: 0962-8436; 1471-2970
• DOI: 10.1098/rstb.2013.0328

The ability to serially interrogate single biomolecules with femtosecond X-ray pulses from free-electron lasers has ushered in the possibility of determining the three-dimensional structure of biomolecules without crystallization. However, the complexity of imaging a sample's structure from very many of its noisy and incomplete diffraction data can be daunting. In this review, we introduce a simple analogue of this imaging workflow, use it to describe a structure reconstruction algorithm based on the expectation maximization principle, and consider the effects of extraneous noise. Such a minimal model can aid experiment and algorithm design in future studies.