Services

NatX can provide a large number of services for protein crystallography. Starting from a protein purified to crystallography grade, it includes typically all or part of the steps described below. For a specific set of services that matches your needs, please, ask for a quotation (contact information).

 

Protein production/purification

This step will be subcontrated to an industrial partner.

Quality control

We use mass spectrometry to check the quality of the sample, before any crystalization attempt. Optional RMN 1D or N-term sequencing is also available.

crystallization assay with standard/nanodrop robots

We use exclusively vapor diffusion sitting drops techniques. We ca help you to define the best condition in which your protein can be stored before crystallization. Depending on the amount of protein available, either 1+1 μL drops (Tecan robot) or 0.1+0.1 μL drops (Cartesian robot) will be used. A standard set of 600 crystallization conditions was selected, but most of the popular commercialy available screens are possible. The crystallization drops will then be controled manualy on a regular basis.
Specific: crystallization in glove box (no oxygen) is also possible.

X-ray screening of the crystallization plates on synchrotron beamlines

Crystallization plates will be screened directly in the X-ray beam on a beamline. Information, such as diffracting resolution, cell parameters, space group and mosaicity will be obtained in situ, without need for fishing and freezing the crystals.

optimisation of the best hits

Best diffracting crystals will be optimized with a specifis creen built around the selected conditions (one plate with up to 4 conditions, each one with six different precipitent conditions and four different pH values). The plate will be screened as previously. The best crystals will be reproduced and frozen, testing different cryo-protectents
Specific: preparation of heavy atom derivatives is also possible.

data collection on synchrotron beamlines, data reduction

A complete, single wavelength, data set will be collected on a synchrotron beamline, and reduced/scaled using XDS package.
Specific: MAD (Multiwavelength Anomalous Diffraction) data collection is also possible.

phasing

MR (Molecular Replacement) or SAD (Single Anomalous Diffraction) phasing will be carried on.
Specific: MAD (Multiwavelength Anomalous Diffraction) phasing is also possible.

refinement, model building

Model will be built and refined against dataset.

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