# OVERVIEW

BACK

The MX2 beamline is an experimental station dedicated to Macromolecular Crystallography in the hard x-rays energy range (5 to 15 keV) with maximum flux at 8.5 keV. The station is available for conventional single wavelength data collection as well as for Single and Multiple-wavelength Anomalous Diffraction (SAD/MAD) experiments. Major improvements will be available in 2017.

MX2 operates on a 2.0 T hybrid 30-pole wiggler and its optical layout includes collimating mirror, Si(111) double-crystal monochromator and toroidal bendable mirror. The beamline is equipped with PILATUS2M detector from Dectris.

The research projects developed at the MX2 beamline yield precise information about the atomic constitution and shape of macromolecules, such as enzymes and membrane-bound proteins, the building blocks of life inside and outside living cells. This information can lead to a fuller understanding of the biological processes carried by these molecules and by consequence, to the development of new and more efficient medications, cosmetics, biofuels and biomaterials.

Starting from a protein crystal, researchers can obtain information about the three-dimensional shape of the protein, and also run screening studies, where atomic details of small molecules that interact with the protein under study can reveal new avenues for the design of inhibitors. These studies can reveal the detailed mechanisms of the interactions between substrates and enzymes, suggesting improvement or inhibition routes that can guide synthetic or natural products chemists in the development of new commodities.

## CONTACT

Beamline Email: N/A

Beamline Telephone Number: +55 19 3512 1245

Coordinator: Ana Carolina de Mattos Zeri

Coordinator Email: ana.zeri@lnls.br

Coordinator Telephone Number: +55 19 3518 2498

For more information on the Beamline Team, check out the Beamline Team’s page here

# OPTICAL ELEMENTS

ElementTypePosition[m]Description
SOURCEInsertion Device0.00Insertion Device W01A, 2.0 T hybrid 30-pole Wiggler, 22 mm minimal gap
M1Cylindrical Vertical Collimating Mirror11.00Rh coated ULE glass, $\theta$=4 mrad
MonoDouble Crystal Monochromator14.26Water-cooled Si(111)
M2Toroidal Horizontal and Vertical Focusing Mirror16.00Rh coated silicon, $\theta$=4 mrad, mechanical bender.

# PARAMETERS

ParameterValueObs. | Condition
Energy range [keV]5-15Si(111)
Energy resolution [$\Delta$E/E]$10^{-4}$Si(111)
Beam size at sample [$\mu \rm m^{2}$, FWHM]150 x 500at 8.5 keV
Beam divergence at sample [$\rm mrad^{2}$, FWHM]3 mradat 8.5 keV
Flux density at sample [ph/s/$\rm mm^{2}$]$10^{11}$at 8.5 keV

# INSTRUMENTATION

InstrumentTypeModelSpecificationsManufacturer
DetectorAreaPILATUS2M$172 \mu \rm m$ pixel, 1475 x 1679 pixel, 30 kHz frame rateDectris
DiffractometerData collectionMarDTBPhi and theta rotations. Ionizations chambers, slits, shutter and sample holding. Detector translation range 100 to 350 mm.Rayonics
CryostatsNitrogenCryojet XLSample cooling at 100 Kelvin.Oxford
DetectorFluorescenceX-123SDDSi drift diode (SDD). Energy resolution 125 to 140 eV FWHM at 5.9 KeV. Maximum count rate $4 \times 10^{6} \rm s^{-1}$. Channels number 8. Communication via EthernetAmptek

# CONTROL AND DATA ACQUISITION

The optical controls are done through EPICS (Experimental Physics and Industrial Control System), running on a control system called PXI from National Instruments. The experimental control and data collection with the Pilatus 2M detector (Dectris) are done via a RedHat station running the Python based software MXCube. MXCube is the product of an international collaboration for the creation and development of a graphic interface for molecular crystallography beamlines (Gabadinho, J.et al.,2010, J. Synchrotron Rad. 17, 700-707). A mini-kappa goniometer and a robot for in-plate data collection are currently under commissioning.

There are also two machines with RedHat workstation to access one Virtual Machine with the following software applications available for data treatment: iMOSFLM (v1.0.5); HKL2000* (v0.98.695B); CCP4 PACKAGE; SHELX; HKL2MAP (v0.2); PHENIX (v1.7); CNS; COOT; PYMOL; SHARP.

* The HKL-2000 program package available at the beamline is provided on the basis of scientific collaboration free of charge by the program Authors.

The use of the package should be referenced in publication as follows: Z. Otwinowski and W. Minor “Processing of X-ray Diffraction Data Collected in Oscillation Mode”, Methods in Enzymology, Volume 276: Macromolecular Crystallography, part A, p. 307-326, 1997, C.W. Carter, Jr. and R.M. Sweet, Eds., Academic Press.

Researchers who perform non-commercial research may freely use the program for data evaluation and processing while collecting data at the beamline. Researchers from institutions who want to use the program for data evaluation and processing for commercial purposes while collecting data on LNLS beamlines must have an appropriate HKL-2000 license. The license can be obtained from HKL Research, Inc.  The HKL-2000 package development is supported by the NIH grant GM-53163 to the laboratories of Drs. Zbyszek Otwinowski (Southwester Medical Center at Dallas) and Wladek Minor (University of Virginia).

# APPLYING FOR BEAMTIME

Submission calls are usually announced twice per year, one for each semester. All the academic research proposals must be submitted electronically through the SAU Online portal. Learn more about how to submit a proposal here.