Evaluating the intrinsic cysteine redox-dependent states of the A-chain of human insulin using NMR spectroscopy, quantum chemical calculations, and mass spectrometry.

ABSTRACT: Previous functional studies have proposed that solution-phase loading of human insulin A-chain peptides into cell surface Class II molecules may be limited by the redox state of intrinsic cysteine residues within the A-chain peptide. T cell functional studies of a human insulin A-chain analogue (KR A1-15) comprised of residues 1-15 of the A-chain peptide as well as an amino-terminal lysine-arginine extension have been carried out in a reducing environment. These data suggest that free thiol moieties within this peptide may participate in major histocompatibility complex (MHC) II/peptide interactions. Two-dimensional (1)H NMR spectroscopy data partnered with quantum chemical calculations identified that KR A1-15 exists in conformational flux sampling heterogeneous redox-dependent conformati

SUBMITTER: Sharma AK 

PROVIDER: S-EPMC2829747 | biostudies-literature | 2010 Jan

REPOSITORIES: biostudies-literature