Photoreduction and validation of haem–ligand intermediate states in protein crystals by in situ single-crystal spectroscopy and diffraction

IUCrJ

Worrall, J.A.R.¹  Kekilli, D.¹  Moreno-Chicano, T.¹  Strange, R.W.¹  Chaplin, A.K.¹  Horrell, S.¹  Hough, M.A.¹  Dworkowski, F.S.N.² 

[1] School of Biological Sciences, University of Essex, Wivenhoe Park, Colchester CO4 3SQ, England;Swiss Light Source, Paul Scherrer Institut, 5232 Villigen-PSI, Switzerland

关键词: X-RAY PHOTOREDUCTION;    LASER PHOTOREDUCTION OF HAEM;    HAEM;    IN CRYSTALLO OPTICAL SPECTROSCOPY;   

DOI  :  10.1107/S2052252517002159

学科分类：数学（综合）

来源: International Union of Crystallography

【 摘 要 】

Powerful synergies are available from the combination of multiple methods to study proteins in the crystalline form. Spectroscopies which probe the same region of the crystal from which X-ray crystal structures are determined can give insights into redox, ligand and spin states to complement the information gained from the electron-density maps. The correct assignment of crystal structures to the correct protein redox and ligand states is essential to avoid the misinterpretation of structural data. This is a particular concern for haem proteins, which can occupy a wide range of redox states and are exquisitely sensitive to becoming reduced by solvated electrons generated from interactions of X-rays with water molecules in the crystal. Here, single-crystal spectroscopic fingerprinting has been applied to investigate the laser photoreduction of ferric haem in cytochrome c′. Furthermore, in situ X-ray-driven generation of haem intermediates in crystals of the dye-decolourizing-type peroxidase A (DtpA) from Streptomyces lividans is described.

【 授权许可】

CC BY