These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


Pubmed for Handhelds

PUBMED FOR HANDHELDS

Search MEDLINE/PubMed

  • Title: Site-directed mutagenesis and 1H nuclear magnetic resonance of an anti-dinitrophenyl spin label antibody.
    Author: Martinez-Yamout M, McConnell HM.
    Journal: J Mol Biol; 1994 Dec 02; 244(3):301-18. PubMed ID: 7966341.
    Abstract:
    Mutagenesis and spin label difference spectroscopy are used to assign the resonances of tyrosine residues in the binding site of the anti-dinitrophenyl spin label (DNP-SL) antibody AN02. Hapten binding constants of 13 point mutants are determined. From these studies it is clear that a light chain tyrosine specifically stabilizes DNP-SL binding, perhaps by means of a hydrogen bond to the hapten. This bond is absent in the case of the diamagnetic hapten dinitrophenyl-diglycine (DNP-Gly2). AN02 mutants with approximately 50 and 200-fold enhanced affinities for DNP-Gly2 are engineered. In these mutants, a single amino acid change relieves an electrostatic interaction between DNP-Gly2 and the binding site. The resulting improvement in hapten binding ability is specific to DNP-Gly2, since the affinity for DNP-SL is relatively unchanged. Evidence of conformational heterogeneity in the AN02/DNP-Gly2 complex is presented. In contrast with DNP-Gly, a ring proton of DNP-Gly2 experiences two environments on binding to AN02. It was previously shown that a light chain tyrosine (LY31) also assumes two conformations when DNP-Gly2 is bound. The simultaneous presence of multiple AN02/DNP-Gly2 complexes implies conformational isomerism of a tryptophan residue which contacts both the hapten and LY31.
    [Abstract] [Full Text] [Related] [New Search]