Long-range-distance NMR effects in a protein labeled with a lanthanide-DOTA chelate.
A two-thiol reactive lanthanide-DOTA (1,4,7,10-tetraazacyclododecane-N,N',N'',N'''-tetraacetic acid) chelate, CLaNP-3 (CLaNP=caged lanthanide NMR probe), was synthesized for the rigid attachment to cysteine groups on a protein surface, and used to obtain long-range-distance information from the {15N,1H} HSQC spectra of the protein-lanthanide complex. The DOTA ring exhibits several isomers that are in exchange; however, single resonances were observed for most amide groups in the protein, allowing determination of a single, apparent magnetic-susceptibility tensor. Pseudocontact shifts caused by Yb-containing CLaNP-3 were observed for atoms at 15-35 A from the metal. By using Gd-containing CLaNP-3, relaxation effects were observed, allowing distances up to 30 A from the paramagnetic center to be determined accurately. Similar results were obtained with a Gd-DTPA (diethylene-triaminepentaacetic acid) chelate, CLaNP-1, bound in the same bidentate manner to the protein. This study demonstrates that bidentate attachment of a paramagnetic probe enables determination of long-range distances.
Vlasie
Monica D
MD
Leiden Institute of Chemistry, Gorlaeus Laboratories Leiden University, P.O. Box 9502, 2300 RA Leiden, The Netherlands.
Comuzzi
Clara
C
van den Nieuwendijk
Adrianus M C H
AM
Prudêncio
Miguel
M
Overhand
Mark
M
Ubbink
Marcellus
M
D002614:Chelating Agents / Q000737:chemistry*; D005682:Gadolinium / Q000737:chemistry; D019786:Gadolinium DTPA / Q000737:chemistry*; D006573:Heterocyclic Compounds, 1-Ring / Q000737:chemistry*; D028581:Lanthanoid Series Elements / Q000737:chemistry*; D009682:Magnetic Resonance Spectroscopy / Q000379:methods; D015394:Molecular Structure; D011506:Proteins / Q000737:chemistry*; D013194:Staining and Labeling
D002614:Chelating Agents; D006573:Heterocyclic Compounds, 1-Ring; D028581:Lanthanoid Series Elements; D011506:Proteins; C071349:1,4,7,10-tetraazacyclododecane- 1,4,7,10-tetraacetic acid; D005682:Gadolinium; D019786:Gadolinium DTPA