Towards structure determination of neurotoxin II bound to nicotinic acetylcholine receptor: a solid-state NMR approach.
Solid-state magic-angle spinning nuclear magnetic resonance (NMR) has sufficient resolving power for full assignment of resonances and structure determination of immobilised biological samples as was recently shown for a small microcrystalline protein. In this work, we show that highly resolved spectra may be obtained from a system composed of a receptor-toxin complex. The NMR sample used for our studies consists of a membrane preparation of the nicotinic acetylcholine receptor from the electric organ of Torpedo californica which was incubated with uniformly 13C-,15N-labelled neurotoxin II. Despite the large size of the ligand-receptor complex ( > 290 kDa) and the high lipid content of the sample, we were able to detect and identify residues from the ligand. The comparison with solution NMR data of the free toxin indicates that its overall structure is very similar when bound to the receptor, but significant changes were observed for one isoleucine.
Krabben
Ludwig
L
Forschungsinstitut für Molekulare Pharmakologie, Robert-Rössle-Strasse 10, D-13125 Berlin, Germany. krabben@fmp-berlin.de
van Rossum
Barth-Jan
BJ
Castellani
Federica
F
Bocharov
Eduard
E
Schulga
Alexey A
AA
Arseniev
Alexander S
AS
Weise
Christoph
C
Hucho
Ferdinand
F
Oschkinat
Hartmut
H
D000818:Animals; D002038:Bungarotoxins / Q000737:chemistry / Q000378:metabolism; D003039:Cobra Neurotoxin Proteins / Q000737:chemistry* / Q000378:metabolism; D008051:Lipid Bilayers / Q000737:chemistry; D046911:Macromolecular Substances; D008958:Models, Molecular; D019906:Nuclear Magnetic Resonance, Biomolecular; D011485:Protein Binding; D017433:Protein Structure, Secondary; D011869:Radioligand Assay; D011978:Receptors, Nicotinic / Q000737:chemistry* / Q000378:metabolism; D014101:Torpedo
D002038:Bungarotoxins; D003039:Cobra Neurotoxin Proteins; D008051:Lipid Bilayers; D046911:Macromolecular Substances; D011978:Receptors, Nicotinic; C076649:neurotoxin II, Naja naja oxiana