A comprehensive calorimetric investigation of an entropically driven T cell receptor-peptide/major histocompatibility complex interaction.

ABSTRACT: The alphabeta T cell receptor (TCR) is responsible for recognizing peptides bound and "presented" by major histocompatibility complex (MHC) molecules. We recently reported that at 25 degrees C the A6 TCR, which recognizes the Tax peptide presented by the class I MHC human leukocyte antigen-A*0201 (HLA-A2), binds with a weak DeltaH degrees , a favorable DeltaS degrees , and a moderately negative DeltaC(p). These observations were of interest given the unfavorable binding entropies and large heat capacity changes measured for many other TCR-ligand interactions, suggested to result from TCR conformational changes occurring upon binding. Here, we further investigated the A6-Tax/HLA-A2 interaction using titration calorimetry. We found that binding results in a pK(a) shift, complicating interpre

SUBMITTER: Armstrong KM 

PROVIDER: S-EPMC1896243 | biostudies-literature | 2007 Jul

REPOSITORIES: biostudies-literature