Different 3D domain-swapped oligomeric cyanovirin-N structures suggest trapped folding intermediates.

ABSTRACT: Although it has long been established that the amino acid sequence encodes the fold of a protein, how individual proteins arrive at their final conformation is still difficult to predict, especially for oligomeric structures. Here, we present a comprehensive characterization of oligomeric species of cyanovirin-N that all are formed by a polypeptide chain with the identical amino acid sequence. Structures of the oligomers were determined by X-ray crystallography, and each one exhibits 3D domain swapping. One unique 3D domain-swapped structure is observed for the trimer, while for both dimer and tetramer, two different 3D domain-swapped structures were obtained. In addition to the previously identified hinge-loop region of the 3D domain-swapped dimer, which resides between strands β5 and β6

SUBMITTER: Koharudin LM 

PROVIDER: S-EPMC3651430 | biostudies-literature | 2013 May

REPOSITORIES: biostudies-literature