Open Access1 H‐NMR conformational analysis of a high‐affinity antigenic 11‐residue peptide from the tryptophan synthase β 2 subunit
Author(s) -
DELEPIERRE Muriel,
LARVOR MariePierre,
BALEUX Françoise,
GOLDBERG Michel E.
Publication year - 1991
Publication title -
european journal of biochemistry
Language(s) - English
Resource type - Journals
eISSN - 1432-1033
pISSN - 0014-2956
DOI - 10.1111/j.1432-1033.1991.tb16329.x
Subject(s) - peptide , tryptophan synthase , chemistry , stereochemistry , cyclic peptide , nuclear magnetic resonance spectroscopy , amide , tryptophan , nuclear overhauser effect , residue (chemistry) , protein subunit , two dimensional nuclear magnetic resonance spectroscopy , amino acid , biochemistry , gene
Two synthetic peptides from the β 2 subunit of tryptophan synthase have been studied by 1 H‐NMR spectroscopy at 300 MHz. One peptide, His‐Gly‐Arg‐Val‐Gly‐Ile‐Tyr‐Phe‐Gly‐Met‐Lys (peptide 11; Ile, isoleucine) is antigenic and binds with a high affinity to a monoclonal antibody that recognizes the native β 2 subunit. The second peptide, His‐Gly‐Arg‐Val‐Gly‐Ile‐Tyr‐Phe (peptide 8) reacts very weakly with the antibody. The 1 H‐NMR spectra of the two peptides have been assigned from two‐dimensional techniques in H 2 O, 2 H 2 O and ( 2 H 6 ) dimethyl sulfoxide [( 2 H 6 )Me 2 SO]. The structure has been evaluated through analysis of nuclear Overhauser effects, coupling constants, amide‐proton exchange rates and their temperature coefficients, and chemical shifts. In aqueous solvent, the C‐terminal part of peptide 11 presents some structure centered around residues Phe‐Gly‐Met. The relationship between the structure found in peptide 11 and its antigenic nature is discussed.