Residual dipolar coupling derived orientational constraints on ligand geometry in a 53 kDa protein-ligand complex.


Journal Article

The geometric relationships between ligands and the functional groups that bind ligands in soluble ligand-protein complexes have traditionally been deduced from distance constraints between pairs of NMR active nuclei spanning the ligand-protein interface. Frequently, the steep inverse distance dependence of the nuclear Overhauser effect (NOE), from which the distance constraints are derived, makes identification of sufficient numbers of constraints difficult. In these cases the ability to supplement NOE-derived information with distance-independent angular information can be very important. Here, the observation of residual dipolar couplings from alpha-methyl mannose bound to mannose binding-protein in a dilute liquid crystalline medium has allowed the determination of a bound ligand's average orientation. The 3-fold rotational symmetry of mannose-binding protein defines its orientational tensor and obviates the need to determine experimentally the protein's average orientation. Through superimposition of ligand and protein orientational tensors we describe the binding geometry of alpha-methyl mannose bound to mannose-binding protein. This new method is of general applicability to the study of ligands bound to proteins, and it is of particular interest when neither X-ray crystallography nor NOE techniques can provide sufficient information to describe binding geometries.

Full Text

Duke Authors

Cited Authors

  • Bolon, PJ; Al-Hashimi, HM; Prestegard, JH

Published Date

  • October 15, 1999

Published In

Volume / Issue

  • 293 / 1

Start / End Page

  • 107 - 115

PubMed ID

  • 10512719

Pubmed Central ID

  • 10512719

International Standard Serial Number (ISSN)

  • 0022-2836

Digital Object Identifier (DOI)

  • 10.1006/jmbi.1999.3133


  • eng

Conference Location

  • England