Kinetics of irreversible dissociation for proteins bound cooperatively to DNA

✍ Scribed by Anna C. Balazs; Irving R. Epstein

• Publisher: Wiley (John Wiley & Sons)
• Year: 1984
• Tongue: English
• Weight: 461 KB
• Volume: 23
• Category: Article
• ISSN: 0006-3525
• DOI: 10.1002/bip.360230709

✦ Synopsis

Synopsis

We consider the irreversible dissociation kinetics of proteins that bind cooperatively and nonspecifically to DNA. Our model consists of an infinitely long one-dimensional nucleic acid lattice on which are bound protein ligands. A set of adjacent bound proteins forms a cluster of length n. A protein molecule may dissociate from any site within the bound cluster, not only from the ends, as was assumed in a previous model of this process due to Lohman "1983) Biopolymers 22,1697-17131. By considering this additional pathway, we present a more general treatment of the dissociation kinetics of cooperatively bound ligands. We show that dissociation from the (n-2) internal positions of an ncluster is an important pathway when the initial fractional saturation of the lattice is close to unity and the cooperativity is low. When the fractional saturation is initially equal to 1 and the cooperativity is low, our model does not give the zero-order dissociation kinetics predicted by the Lohman model.