Download MendeleyEllman's reagent in promoting crystallization and structure determination of Anabaena CcbP.
Fan, X.X., Zhou, Y.F., Liu, X., Li, L.F., Su, X.D.(2012) Acta Crystallogr Sect F Struct Biol Cryst Commun 68: 1409-1414
- PubMed: 23143261
- DOI: https://doi.org/10.1107/S1744309112034938
- Primary Citation of Related Structures:
3URG - PubMed Abstract:
Obtaining crystals presented a bottleneck in the structural study of Anabaena cyanobacterial Ca2+-binding protein (CcbP). In this report, the promoting effect of Ellman's reagent [5,5'-dithiobis(2-nitrobenzoic acid); DTNB] on the crystallization of CcbP is described. CcbP contains one free cysteine. A quick and simple oxidation reaction with DTNB blocked the free cysteine in purified CcbP and generated a homogenous monomeric protein for crystallization. The crystal structure of DTNB-modified CcbP was determined by the single-wavelength anomalous diffraction method. Structure analysis indicated that DTNB modification facilitated crystallization of CcbP by inducing polar interactions in the crystal lattice. DTNB-mediated cysteine modification was demonstrated to have little effect on the overall structure and the Ca2+ binding of CcbP. Thus, DTNB modification may provide a simple and general approach for protein modification to improve the success of crystallization screening.
Organizational Affiliation:
State Key Laboratory of Protein and Plant Gene Research, and Biodynamic Optical Imaging Center (BIOPIC), School of Life Sciences, Peking University, No. 5 Yiheyuan Road, Beijing 100871, People's Republic of China.
