4V3R: Designed Armadillo Repeat Protein With 5 Internal Repeats, 2nd Generation C-cap And 3rd Generation N-cap

The armadillo repeat serves as a scaffold for the development of modular peptide-recognition modules. In order to develop such a system, three crystal structures of designed armadillo-repeat proteins with third-generation N-caps (YIII-type), four or five internal repeats (M-type) and second-generation C-caps (AII-type) were determined at 1.8 A (His-YIIIM4AII), 2.0 A (His-YIIIM5AII) and 1.95 A (YIIIM5AII) resolution and compared with those of variants with third-generation C-caps. All constructs are full consensus designs in which the internal repeats have exactly the same sequence, and hence identical conformations of the internal repeats are expected. The N-cap and internal repeats M1 to M3 are indeed extremely similar, but the comparison reveals structural differences in internal repeats M4 and M5 and the C-cap. These differences are caused by long-range effects of the C-cap, contacting molecules in the crystal, and the intrinsic design of the repeat. Unfortunately, the rigid-body movement of the C-terminal part impairs the regular arrangement of internal repeats that forms the putative peptide-binding site. The second-generation C-cap improves the packing of buried residues and thereby the stability of the protein. These considerations are useful for future improvements of an armadillo-repeat-based peptide-recognition system.
PDB ID: 4V3RDownload
MMDB ID: 135326
PDB Deposition Date: 2014/10/20
Updated in MMDB: 2016/03
Experimental Method:
x-ray diffraction
Resolution: 1.95  Å
Source Organism:
Similar Structures:
Biological Unit for 4V3R: monomeric; determined by author and by software (PISA)
Molecular Components in 4V3R
Label Count Molecule
Protein (1 molecule)
Molecule annotation
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Citing MMDB