4x0k

Engineered Fab fragment specific for EYMPME (EE) peptideEngineered Fab fragment specific for EYMPME (EE) peptide

Structural highlights 4x0k is a 4 chain structure with sequence from Homo sapiens. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance. Method: X-ray diffraction, Resolution 2.04Å Resources: FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT Publication Abstract from PubMed Crystallization chaperones are attracting increasing interest as a route to crystal growth and structure elucidation of difficult targets such as membrane proteins. While strategies to date have typically employed protein-specific chaperones, a peptide-specific chaperone to crystallize multiple cognate peptide epitope-containing client proteins is envisioned. This would eliminate the target-specific chaperone-production step and streamline the co-crystallization process. Previously, protein engineering and directed evolution were used to generate a single-chain variable (scFv) antibody fragment with affinity for the peptide sequence EYMPME (scFv/EE). This report details the conversion of scFv/EE to an anti-EE Fab format (Fab/EE) followed by its biophysical characterization. The addition of constant chains increased the overall stability and had a negligible impact on the antigen affinity. The 2.0 A resolution crystal structure of Fab/EE reveals contacts with larger surface areas than those of scFv/EE. Surface plasmon resonance, an enzyme-linked immunosorbent assay, and size-exclusion chromatography were used to assess Fab/EE binding to EE-tagged soluble and membrane test proteins: namely, the beta-barrel outer membrane protein intimin and alpha-helical A2a G protein-coupled receptor (A2aR). Molecular-dynamics simulation of the intimin constructs with and without Fab/EE provides insight into the energetic complexities of the co-crystallization approach. Structural and biophysical characterization of an epitope-specific engineered Fab fragment and complexation with membrane proteins: implications for co-crystallization.,Johnson JL, Entzminger KC, Hyun J, Kalyoncu S, Heaner DP Jr, Morales IA, Sheppard A, Gumbart JC, Maynard JA, Lieberman RL Acta Crystallogr D Biol Crystallogr. 2015 Apr;71(Pt 4):896-906. doi:, 10.1107/S1399004715001856. Epub 2015 Mar 27. PMID:25849400 From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.

spinqualitylabelsall models 4x0k, resolution 2.04Å Show:Asymmetric Unit Biological Assembly Drag the structure with the mouse to rotate   Export Animated Image