Characterization of gadolinium complexes for SAD phasing in macromolecular crystallography: application to CbpF

• Published in: Acta crystallographica. Section D, Biological crystallography. Vol. 65; no. 8; pp. 823 - 831
• Main Authors: Molina, Rafael, Stelter, Meike, Kahn, Richard, Hermoso, Juan A.
• Format: Journal Article
• Language: English
• Published: 5 Abbey Square, Chester, Cheshire CH1 2HU, England International Union of Crystallography 01-08-2009
• Subjects: Bacterial Proteins - chemistry; Bacterial Proteins - metabolism; Carrier Proteins - chemistry; Carrier Proteins - metabolism; Choline - metabolism; choline-binding protein; Crystallization; Gadolinium - chemistry; Gadolinium - metabolism; gadolinium complexes; Macromolecular Substances - chemistry; Macromolecular Substances - metabolism; Protein Binding; Protein Conformation; SAD phasing; Streptococcus pneumoniae; Sulfur - chemistry; Sulfur - metabolism; Synchrotrons; X-Ray Diffraction
• ISSN: 1399-0047; 0907-4449; 1399-0047
• DOI: 10.1107/S0907444909017958

Seven Gd complexes were used in the preparation of heavy‐atom derivatives for solving the structure of choline‐binding protein F (CbpF), a 36 kDa surface protein from Streptococcus pneumoniae, by the SAD method. CbpF was used as a model system to analyse the phasing capability of each of the derivatives. Three different aspects have been systematically characterized: the efficacy of cocrystallization versus soaking in the binding of the different Gd complexes, their mode of interaction and a comparative study of SAD phasing using synchrotron radiation and using a rotating‐anode generator. This study reveals the striking potential of these complexes for SAD phasing using a laboratory source and further reinforces their relevance for high‐throughput macromolecular crystallography.