Reconstruction from limited single-particle diffraction data via simultaneous determination of state, orientation, intensity, and phase

Significance Single-particle diffraction is an emerging technique in which diffraction images are collected from individual particles, and is used to study molecular structure from multiple conformational states that may be inaccessible through other methods. However, determining structure from these experiments is challenging, since orientations and states of imaged particles are unknown and images are highly contaminated with noise. Furthermore, the number of useful images is often limited by achievable single-particle hit rates, currently around 0.1%. We introduce an iterative projection framework to simultaneously determine orientations, states, and molecular structure from limited single-particle data by leveraging structural constraints throughout the reconstruction. This framework offers a potential pathway to increasing the amount of information that can be extracted from single-particle diffraction. Free-electron lasers now have the ability to collect X-ray diffraction patterns from individual molecules; however, each sample is delivered at unknown orientation and may be in one of several conformational states, each with a different molecular structure. Hit rates are often low, typically around 0.1%, limiting the number of useful images that can be collected. Determining accurate structural information requires classifying and orienting each image, accurately assembling them into a 3D diffraction intensity function, and determining missing phase information. Additionally, single particles typically scatter very few photons, leading to high image noise levels. We develop a multitiered iterative phasing algorithm to reconstruct structural information from single-particle diffraction data by simultaneously determining the states, orientations, intensities, phases, and underlying structure in a single iterative procedure. We leverage real-space constraints on the structure to help guide optimization and reconstruct underlying structure from very few images with excellent global convergence properties. We show that this approach can determine structural resolution beyond what is suggested by standard Shannon sampling arguments for ideal images and is also robust to noise.

[1]  A. Ourmazd,et al.  Structure from Fleeting Illumination of Faint Spinning Objects in Flight with Application to Single Molecules , 2008, 0806.2341.

[2]  M. Burghammer,et al.  Crystal structure of the retinoblastoma tumor suppressor protein bound to E2F and the molecular basis of its regulation , 2003, Proceedings of the National Academy of Sciences of the United States of America.

[3]  K. Schmidt,et al.  Gas dynamic virtual nozzle for generation of microscopic droplet streams , 2008, 0803.4181.

[4]  J. Navaza,et al.  Fast projection matching for cryo-electron microscopy image reconstruction. , 2008, Journal of structural biology.

[5]  S A Bobkov,et al.  Sorting algorithms for single-particle imaging experiments at X-ray free-electron lasers. , 2015, Journal of synchrotron radiation.

[6]  A. Ourmazd,et al.  Crystallography without crystals. I. The common-line method for assembling a three-dimensional diffraction volume from single-particle scattering. , 2008, Acta crystallographica. Section A, Foundations of crystallography.

[7]  Andrew G. Watts,et al.  Conservation of Structure and Mechanism in Primary and Secondary Transporters Exemplified by SiaP, a Sialic Acid Binding Virulence Factor from Haemophilus influenzae* , 2006, Journal of Biological Chemistry.

[8]  Anton Barty,et al.  High-throughput imaging of heterogeneous cell organelles with an X-ray laser , 2014, Nature Photonics.

[9]  S. Marchesini,et al.  Invited article: a [corrected] unified evaluation of iterative projection algorithms for phase retrieval. , 2006, The Review of scientific instruments.

[10]  G. Bortel,et al.  Common arc method for diffraction pattern orientation. , 2011, Acta crystallographica. Section A, Foundations of crystallography.

[11]  N. Loh,et al.  Reconstruction algorithm for single-particle diffraction imaging experiments. , 2009, Physical review. E, Statistical, nonlinear, and soft matter physics.

[12]  Jean-Michel Claverie,et al.  Three-dimensional reconstruction of the giant mimivirus particle with an x-ray free-electron laser. , 2015, Physical review letters.

[13]  Jorge Navaza On the three-dimensional reconstruction of icosahedral particles. , 2003, Journal of structural biology.

[14]  D. DeRosier,et al.  The reconstruction of a three-dimensional structure from projections and its application to electron microscopy , 1970, Proceedings of the Royal Society of London. A. Mathematical and Physical Sciences.

[15]  J. Rost,et al.  Enhancing scattering images for orientation recovery with diffusion map. , 2016, Optics express.

[16]  A. Ourmazd,et al.  The Symmetries of Image Formation by Scattering , 2010 .

[17]  A. Ourmazd,et al.  High-resolution structure of viruses from random diffraction snapshots , 2014, Philosophical Transactions of the Royal Society B: Biological Sciences.

[18]  I. A. Vartanyants,et al.  Orientation determination in single-particle x-ray coherent diffraction imaging experiments , 2013, 1302.5730.

[19]  S Marchesini,et al.  Invited article: a [corrected] unified evaluation of iterative projection algorithms for phase retrieval. , 2006, The Review of scientific instruments.

[20]  Peter Schwander,et al.  The symmetries of image formation by scattering. I. Theoretical framework. , 2010, Optics express.

[21]  Julien Flamant,et al.  Expansion-maximization-compression algorithm with spherical harmonics for single particle imaging with x-ray lasers. , 2016, Physical review. E.

[22]  D. Ratner,et al.  First lasing and operation of an ångstrom-wavelength free-electron laser , 2010 .

[23]  Jorge Navaza,et al.  On the fast rotation function , 1987 .

[24]  Garth J. Williams,et al.  Single mimivirus particles intercepted and imaged with an X-ray laser , 2011, Nature.

[25]  S. Marchesini,et al.  X-ray image reconstruction from a diffraction pattern alone , 2003, physics/0306174.

[26]  R. Gerchberg A practical algorithm for the determination of phase from image and diffraction plane pictures , 1972 .

[27]  D. Rockmore,et al.  FFTs on the Rotation Group , 2008 .

[28]  G. Phillips,et al.  Mapping the conformations of biological assemblies , 2009, 0909.5404.

[29]  Gábor Bortel,et al.  Atomic structure of a single large biomolecule from diffraction patterns of random orientations. , 2012, Journal of structural biology.

[30]  S. Provencher,et al.  Three-dimensional reconstruction from electron micrographs of disordered specimens. I. Method. , 1988, Ultramicroscopy.

[31]  Chao Yang,et al.  Orientation determination for 3D single molecule diffraction imaging , 2010, Optical Engineering + Applications.

[32]  Peter H Zwart,et al.  Iterative phasing for fluctuation X-ray scattering , 2015, Proceedings of the National Academy of Sciences.

[33]  M. Sezan,et al.  Tomographic Image Reconstruction from Incomplete View Data by Convex Projections and Direct Fourier Inversion , 1984, IEEE Transactions on Medical Imaging.

[34]  Andrew V. Martin,et al.  Unsupervised classification of single-particle X-ray diffraction snapshots by spectral clustering. , 2011, Optics express.

[35]  J R Fienup,et al.  Reconstruction of an object from the modulus of its Fourier transform. , 1978, Optics letters.