view article

Figure 1
Experimental cycle for protein–ligand complex crystal structure generation. For targets with limited structural information, the cycle starts with selecting suitable start and end points for the protein (subdomain) of interest. The resulting protein fragments can be combined with different expression vectors, adding affinity tags for purification. Not all of these constructs will express equally well, and usually only the subset with sufficient expression levels will be taken forward into purification. Extensive optimization of expression and purification conditions should be weighed against the design of more constructs and the use of different solubilizing and affinity tags. If previous structures of the protein (fragment) are available, the cycle is typically entered at the crystallization or soaking stage. Co-crystallization and soaking is ligand-dependent, even for ligands of similar binding affinity. If available, testing batches of 3–5 similar compounds in parallel is recommended. After a co-crystal structure has been determined, the ligand complex should be carefully checked and, if necessary, the cycle re-entered.

Journal logoSTRUCTURAL
ISSN: 2059-7983
Follow Acta Cryst. D
Sign up for e-alerts
Follow Acta Cryst. on Twitter
Follow us on facebook
Sign up for RSS feeds