5APS: Sequence Ienkkad Inserted Between Gcn4 Adaptors - Structure A7

Coiled coils are the best-understood protein fold, as their backbone structure can uniquely be described by parametric equations. This level of understanding has allowed their manipulation in unprecedented detail. They do not seem a likely source of surprises, yet we describe here the unexpected formation of a new type of fiber by the simple insertion of two or six residues into the underlying heptad repeat of a parallel, trimeric coiled coil. These insertions strain the supercoil to the breaking point, causing the local formation of short beta-strands, which move the path of the chain by 120 degrees around the trimer axis. The result is an alpha/beta coiled coil, which retains only one backbone hydrogen bond per repeat unit from the parent coiled coil. Our results show that a substantially novel backbone structure is possible within the allowed regions of the Ramachandran space with only minor mutations to a known fold.
PDB ID: 5APSDownload
MMDB ID: 135988
PDB Deposition Date: 2015/9/17
Updated in MMDB: 2017/03
Experimental Method:
x-ray diffraction
Resolution: 1.37  Å
Source Organism:
Similar Structures:
Biological Unit for 5APS: trimeric; determined by author and by software (PISA)
Molecular Components in 5APS
Label Count Molecule
Proteins (3 molecules)
General Control Protein Gcn4(Gene symbol: GCN4)
Molecule annotation
* Click molecule labels to explore molecular sequence information.

Citing MMDB