Thermodynamics of T cell receptor binding to peptide-MHC: evidence for a general mechanism of molecular scanning.

ABSTRACT: Antigen-dependent activation of T lymphocytes requires T cell receptor (TCR)-mediated recognition of specific peptides, together with the MHC molecules to which they are bound. To achieve this recognition in a reasonable time frame, the TCR must scan and discriminate rapidly between thousands of MHC molecules differing from each other only in their bound peptides. Kinetic analysis of the interaction between a TCR and its cognate peptide-MHC complex indicates that both association and dissociation depend heavily on the temperature, indicating the presence of large energy barriers in both phases. Thermodynamic analysis reveals changes in heat capacity and entropy that are characteristic of protein-ligand associations in which local folding is coupled to binding. Such an "induced-fit" mechani

SUBMITTER: Boniface JJ 

PROVIDER: S-EPMC18053 | biostudies-literature | 1999 Sep

REPOSITORIES: biostudies-literature