The X-ray facility provides state-of-the-art resources to elucidate three dimensional structures of macromolecules and their complexes at the atomic level. It is equipped with powerful microfocus rotating anode generators: 1) MicroMax™ 007 HF (Rigaku) Cu anode generator with Mar345-dtb image plate detector and Oxford cryosystem 2) FR-E+ SuperBright (Rigaku) dual wavelength Cu/Cr anode generators with R-axis IV++ image plate detector and X-stream cryosystem. FR-E+ system is the most intense home lab source available today for macromolecular crystallography, with focusing optics that can deliver a flux comparable to second generation synchrotron beamlines. Data collected from single crystal diffraction is processed using crystallographic computational software. Molecular-modeling studies are performed using Intel Quad-Core windows and Linux-based workstations, Silicon Graphics (SGI-Fuel) workstations and software that are installed on CCMB server.
High Throughput (HT) Crystallization
A state-of-the-art HT-Crystallization facility provides automation of the complete crystallization set-up. Three major components operational are: (i) Alchemist for liquid handling, (ii) Crystallization robotic systems: Mosquito, Oryx 4 and Hydra II-eDrop for crystallization drop setting and (iii) Minstrel III along with two incubators (4ºC and 20ºC) automated for incubation, storage and inspection of plates for crystal growth. It is supported by dynamic light scattering (DLS), which is a useful tool to diagnose size distribution, stability, and aggregation state of macromolecules in solution prior to crystallization.
Small Angle X-ray Scattering
The facility is also equipped with an in-house Small Angle X-ray Scattering (SAXS) System for deciphering physical and structural features of macromolecules in solution. SAXS allows probing the size, shape, quaternary structure and complex formation of molecules without crystallization. It helps in understanding (i) structural parameters [radius of gyration (Rg), maximum Dimension (Dmax), partial-specific volume (Vp) etc], (ii) dynamics of molecules, and (iii) generation of low-resolution shapes of macromolecules. The SAXS facility houses two systems: 1) S3-MICRO Point-Focus system (Hecus X-ray systems, GmbH) with a 50W X-ray source and a Pilatus-100K detector covering a SAXS range between 2000Å and 10Å. 2) BioSAXS-2000 (Rigaku) with 2-D Kratky collimation, mounted on the existing left port of MicroMax™ 007 HF (Rigaku) Cu anode X-ray generator. It is equipped with OptiSAXS Confocal Max-Flux (CMF) for higher brilliance at the sample position and data collection times in the range of minutes. The configuration incorporates an Automatic Sample Changer for unattended overnight operation and an Automatic Analysis Pipeline based on the ATSAS package from EMBL Hamburg.
