5XCT

Crystal structure of P20.1 Fv-clasp fragment with its antigen peptide

Summary for 5XCT

• Entry DOI: 10.2210/pdb5xct/pdb
• Related: 5XCQ 5XCR 5XCS 5XCT 5XCU 5XCX
• Descriptor: VH(S112C)-SARAH chimera, VL-SARAH(S37C)chimera, C8 peptide, ... (5 entities in total)
• Functional Keywords: antibody fragment, fv-clasp, immune system
• Biological source: Mus musculus; More
• Total number of polymer chains: 3
• Total formula weight: 38084.55

Authors

Arimori, T.,Takagi, J. (deposition date: 2017-03-23, release date: 2017-10-04, Last modification date: 2024-10-16)

Primary citation

Arimori, T.,Kitago, Y.,Umitsu, M.,Fujii, Y.,Asaki, R.,Tamura-Kawakami, K.,Takagi, J.
Fv-clasp: An Artificially Designed Small Antibody Fragment with Improved Production Compatibility, Stability, and Crystallizability
Structure, 25:1611-1622.e4, 2017

PubMed Abstract: Antibody fragments are frequently used as a "crystallization chaperone" to aid structural analysis of complex macromolecules that are otherwise crystallization resistant, but conventional fragment formats have not been designed for this particular application. By fusing an anti-parallel coiled-coil structure derived from the SARAH domain of human Mst1 kinase to the variable region of an antibody, we succeeded in creating a novel chimeric antibody fragment of ∼37 kDa, termed "Fv-clasp," which exhibits excellent crystallization compatibility while maintaining the binding ability of the original IgG molecule. The "clasp" and the engineered disulfide bond at the bottom of the Fv suppressed the internal mobility of the fragment and shielded hydrophobic residues, likely contributing to the high heat stability and the crystallizability of the Fv-clasp. Finally, Fv-clasp antibodies showed superior "chaperoning" activity over conventional Fab fragments, and facilitated the structure determination of an ectodomain fragment of integrin α6β1.

PubMed: 28919443
DOI: 10.1016/j.str.2017.08.011

Experimental method

X-RAY DIFFRACTION (1.17 Å)