Molecular mechanism of domain swapping in proteins: an analysis of slower motions.

ABSTRACT: Domain swapping is a structural phenomenon that plays an important role in the mechanism of oligomerization of some proteins. The monomer units in the oligomeric structure become entangled with each other. Here we investigate the mechanism of domain swapping in diphtheria toxin and the structural criteria required for it to occur by analyzing the slower modes of motion with elastic network models, Gaussian network model and anisotropic network model. We take diphtheria toxin as a representative of this class of domain-swapped proteins and show that the domain, which is being swapped in the dimeric state, rotates and twists, in going from the "open" to the "closed" state, about a hinge axis that passes through the middle of the loop extending between two domains. A combination of the intra-

SUBMITTER: Kundu S 

PROVIDER: S-EPMC1304286 | biostudies-literature | 2004 Jun

REPOSITORIES: biostudies-literature