Micro-crystallography comes of age

Abstract

The latest revolution in macromolecular crystallography was incited by the development of dedicated, user friendly, micro-crystallography beamlines. Brilliant X-ray beams of diameter 20 microns or less, now available at most synchrotron sources, enable structure determination from samples that previously were inaccessible. Relative to traditional crystallography, crystals with one or more small dimensions have diffraction patterns with vastly improved signal-to-noise when recorded with an appropriately matched beam size. Structures can be solved from isolated, well diffracting regions within inhomogeneous samples. This review summarizes the technological requirements and approaches to producing micro-beams and how they continue to change the practice of crystallography.

New methods for indexing multi-lattice diffraction data

“…The development of microfocus beamlines has allowed data to be collected from smaller crystals than ever before [see the recent reviews of the history and capabilities of microfocus beamlines by Evans et al (2011) and Smith et al (2012)]. Frequently, particularly in the cases of viruses and membrane proteins, only small, poor-quality crystals may be available and it may only be possible to collect a highly incomplete data set over a small oscillation range for each individual crystal before the diffraction quality is affected by radiation damage.…”

Protein Micro-Crystallography: Nanotechnology Challenges Ahead

“…Protein microcrystallography (MPX) at 3 rd generation synchrotron radiation (SR) sources [1,2] has provided access to structures which are difficult to crystallize such as amyloids [3] or membrane proteins [4,5]. Technical and scientific progress is dominated by the development of more and more brilliant X-ray sources allowing recording diffraction patterns from increasingly smaller crystals in a shorter time.…”

“…For an overview on other SFX flow-injectors and fixed target supports see: [12].The limited availability of XFELs provides, however, a drive for optimizing SR-MPX beam lines and using both types of sources in a complementary way. Indeed, SR-MPX provides currently access to crystallite volumes down to a few μm 3 [1,2,13] while nm 3 volumes have become accessible at XFELs [9]. Radiation-free XFEL data collection is a dream-come-true for protein crystallographers.…”

In vacuoX-ray data collection from graphene-wrapped protein crystals

“…This is owing to developments in beamline instrumentation, such as pixel-array detector (PAD) technology (Mueller et al, 2012), improved quality of focusing optics (Duke & Johnson, 2010) and higher brightness sources with greater stability. The introduction of microfocus MX beamlines has also helped immensely in this area, satisfying the ever-increasing demand to probe the smallest crystals possible (Evans, Axford, Waterman et al, 2011;Smith et al, 2012;Duran et al, 2013;Fischetti et al, 2013;Hirata et al, 2013;Schneider et al, 2013;Holton & Frankel, 2010).…”