Xray crystallography Lasse Mårtensson, IFM-Chemistry

Xray crystallography

Lasse Mårtensson, IFM-Chemistry

Ribosome

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Diffraction pattern from a protein obtained by xray crystallography

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Electrondensity map

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• Requirements:

• Pure protein of high concentration 10-50 mg/ml AND…

• Protein crystals

How to obtain protein crystals??

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Crystallization robot

Terms used in Xray crystallography

• Crystal system

• Spacegroup

• Unit cell

• Assymmetric unit

• Miller indices hkl

• Braggs law

• Ewald sphere

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Ewald sphere with a radius of 1/All lattice points that touch the lattice obey Bragg´s law

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Refinement of the structure

Quality index

R-factor:

Ramachandran plot