1DWF

Study on radiation damage on a cryocooled crystal. Part 2: Structure after irradiation with 9.1*10e15 photons/mm2

Summary for 1DWF

• Entry DOI: 10.2210/pdb1dwf/pdb
• Related: 1DWA 1DWG 1DWH 1DWI 1DWJ 1MYR
• Descriptor: MYROSINASE MA1, 2-acetamido-2-deoxy-beta-D-glucopyranose-(1-4)-2-acetamido-2-deoxy-beta-D-glucopyranose, beta-D-xylopyranose-(1-2)-beta-D-mannopyranose-(1-4)-2-acetamido-2-deoxy-beta-D-glucopyranose-(1-4)-[alpha-L-fucopyranose-(1-3)]2-acetamido-2-deoxy-beta-D-glucopyranose, ... (9 entities in total)
• Functional Keywords: hydrolase, glycosidase, radiation damage, radiolysis, cryo-cooled
• Biological source: SINAPIS ALBA (WHITE MUSTARD)
• Total number of polymer chains: 1
• Total formula weight: 62372.43

Authors

Burmeister, W.P. (deposition date: 1999-12-05, release date: 2000-03-03, Last modification date: 2023-12-13)

Primary citation

Burmeister, W.P.
Structural Changes in a Cryo-Cooled Protein Crystal due to Radiation Damage
Acta Crystallogr.,Sect.D, 56:328-, 2000

PubMed Abstract: The high intensity of third-generation X-ray sources, along with the development of cryo-cooling of protein crystals at temperatures around 100 K, have made it possible to extend the diffraction limit of crystals and to reduce their size. However, even with cryo-cooled crystals, radiation damage becomes a limiting factor. So far, the radiation damage has manifested itself in the form of a loss of overall diffracted intensity and an increase in the temperature factor. The structure of a protein (myrosinase) after exposure to different doses of X-rays in the region of 20 x 10(15) photons mm(-2) has been studied. The changes in the structure owing to radiation damage were analysed using Fourier difference maps and occupancy refinement for the first time. Damage was obvious in the form of breakage of disulfide bonds, decarboxylation of aspartate and glutamate residues, a loss of hydroxyl groups from tyrosine and of the methylthio group of methionine. The susceptibility to radiation damage of individual groups of the same kind varies within the protein. The quality of the model resulting from structure determination might be compromised owing to the presence of radiolysis in the crystal after an excessive radiation dose. Radiation-induced structural changes may interfere with the interpretation of ligand-binding studies or MAD data. The experiments reported here suggest that there is an intrinsic limit to the amount of data which can be extracted from a sample of a given size.

PubMed: 10713520
DOI: 10.1107/S0907444999016261

Experimental method

X-RAY DIFFRACTION (2 Å)