Orthogonal spin labeling and Gd(III)-nitroxide distance measurements on bacteriophage T4-lysozyme

J Phys Chem B. 2013 Mar 21;117(11):3145-53. doi: 10.1021/jp401806g. Epub 2013 Mar 8.

Abstract

We present the first example of chemoselective site-specific spin labeling of a monomeric protein with two spectroscopically orthogonal spin labels: a gadolinium(III) chelate complex and a nitroxide radical. A detailed analysis of the performance of two commercially available Gd(III) ligands in the Gd(III)-nitroxide pulse double electron-electron resonance (DEER or PELDOR) experiment is reported. A modification of the flip angle of the pump pulse in the Gd(III)-nitroxide DEER experiment is proposed to optimize sensitivity.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Bacteriophage T4 / enzymology*
  • Electron Spin Resonance Spectroscopy
  • Electrons
  • Gadolinium / chemistry*
  • Heterocyclic Compounds, 1-Ring / chemistry
  • Muramidase / chemistry*
  • Muramidase / genetics
  • Muramidase / metabolism
  • Mutation
  • Nitrogen Oxides / chemistry*
  • Spin Labels

Substances

  • Heterocyclic Compounds, 1-Ring
  • Nitrogen Oxides
  • Spin Labels
  • 1,4,7,10-tetraazacyclododecane- 1,4,7,10-tetraacetic acid
  • Gadolinium
  • Muramidase
  • nitroxyl