title: A rapid and rational approach to generating isomorphous heavy-atom phasing derivatives.
abstract: In attempts to replace the conventional trial-and-error heavy-atom derivative search method with a rational approach, we previously defined heavy metal compound reactivity against peptide ligands. Here, we assembled a composite pH- and buffer-dependent peptide reactivity profile for each heavy metal compound to guide rational heavy-atom derivative search. When knowledge of the best-reacting heavy-atom compound is combined with mass spectrometry assisted derivatization, and with a quick-soak method to optimize phasing, it is likely that the traditional heavy-atom compounds could meet the demand of modern high-throughput X-ray crystallography. As an example, we applied this rational heavy-atom phasing approach to determine a previously unknown mouse serum amyloid A2 crystal structure.
authors.affiliation: Structural Immunology Section, Laboratory of Immunogenetics, National Institute of Allergy and Infectious Diseases, Rockville, MD, USA.
authors.forename: Jinghua
authors.initials: J
authors.lastname: Lu
authors.forename: Peter D
authors.initials: PD
authors.lastname: Sun
mesh_terms: D020816:Amino Acid Motifs; D000818:Animals; D003460:Crystallization; D018360:Crystallography, X-Ray / Q000379:methods; D006046:Gold / Q000737:chemistry; D051379:Mice; D008958:Models, Molecular; D010984:Platinum / Q000737:chemistry; D000685:Serum Amyloid A Protein / Q000737:chemistry*
chemical_list: C489995:Saa2 protein, mouse; D000685:Serum Amyloid A Protein; D010984:Platinum; D006046:Gold
keywords: heavy-atom reactivity profiles; mass spectrometry-assisted heavy-atom derivatization; quick-soaking method; rational heavy-atom screen