Fast iodide-SAD phasing for high-throughput membrane protein structure determination

Sci Adv. 2017 May 12;3(5):e1602952. doi: 10.1126/sciadv.1602952. eCollection 2017 May.


We describe a fast, easy, and potentially universal method for the de novo solution of the crystal structures of membrane proteins via iodide-single-wavelength anomalous diffraction (I-SAD). The potential universality of the method is based on a common feature of membrane proteins-the availability at the hydrophobic-hydrophilic interface of positively charged amino acid residues with which iodide strongly interacts. We demonstrate the solution using I-SAD of four crystal structures representing different classes of membrane proteins, including a human G protein-coupled receptor (GPCR), and we show that I-SAD can be applied using data collection strategies based on either standard or serial x-ray crystallography techniques.

Keywords: Membrane protein; SAD; experimental phasing; iodide; serial crystallography; x-ray crystallography.

MeSH terms

  • Crystallography, X-Ray / methods
  • Humans
  • Iodides*
  • Protein Domains
  • Receptors, G-Protein-Coupled / chemistry*
  • Scattering, Small Angle*


  • Iodides
  • Receptors, G-Protein-Coupled