Identification of protein surfaces by NMR measurements with a pramagnetic Gd(III) chelate

J Am Chem Soc. 2002 Jan 23;124(3):372-3. doi: 10.1021/ja016985h.

Abstract

Gd-diethylenetriamine pentaacetic acid-bismethylamide, Gd(DTPA-BMA), is shown to be a reagent suitable for the identification of protein surfaces. Compared to the conventionally used spin-label TEMPOL, Gd(DTPA-BMA) is a stronger relaxation agent, requiring lesser concentrations to achieve the same paramagnetic relaxation enhancement of solvent-exposed protein protons. It is also less hydrophobic and therefore less prone to specific binding to proteins. Relaxation enhancements predicted by a second-sphere interaction model correlated with experimental data recorded with ubiquitin, while the correlation with corresponding data recorded with TEMPOL was poor.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Chelating Agents / chemistry*
  • Cyclic N-Oxides / chemistry
  • Gadolinium DTPA / chemistry*
  • Humans
  • Nuclear Magnetic Resonance, Biomolecular / methods*
  • Proteins / chemistry*
  • Spin Labels
  • Surface Properties
  • Ubiquitin / chemistry

Substances

  • Chelating Agents
  • Cyclic N-Oxides
  • Proteins
  • Spin Labels
  • Ubiquitin
  • gadodiamide
  • Gadolinium DTPA
  • tempol