Kinetics of contact formation and end-to-end distance distributions of swollen disordered peptides.

ABSTRACT: Unstructured polypeptide chains are subject to various degrees of swelling or compaction depending on the combination of solvent condition and amino acid sequence. Highly denatured proteins generally behave like random-coils with excluded volume repulsion, whereas in aqueous buffer more compact conformations have been observed for the low-populated unfolded state of globular proteins as well as for naturally disordered sequences. To quantitatively account for the different mechanisms inducing the swelling of polypeptides, we have examined three 14-residues peptides in aqueous buffer and in denaturant solutions, including the well characterized AGQ repeat as a reference and two variants, in which we have successively introduced charged side chains and removed the glycines. Quenching of the

SUBMITTER: Soranno A 

PROVIDER: S-EPMC2717228 | biostudies-literature | 2009 Feb

REPOSITORIES: biostudies-literature