A 15n-filtered 2D 1H TOCSY experiment for assignment of aromatic ring resonances and selective identification of tyrosine ring resonances in proteins: Description and application to Photoactive Yellow Protein.
A new method to selectively detect the ring resonances of the aromatic residues in 15N-labelled proteins is presented. The experiment consists of a 2D 1H TOCSY sequence withremoval of the amide signals via 15N-filtering. Experiments are acquired in the absence andpresence of water inversion; combining the two spectra allows selective observation of thetyrosine ring resonances and enables the identification of their delta andepsilon ring protons. The experiment is demonstrated on a 15N-labelled sample of Photoactive Yellow Protein and isshown to give good selectivity for tyrosine ring resonances under a wide range oftemperatures and pH values.
Whitehead
B
B
Bijvoet Center for Biomolecular Research, Utrecht University, Padualaan 8, 3584 CH, Utrecht, The Netherlands.
Tessari
M
M
Düx
P
P
Boelens
R
R
Kaptein
R
R
Vuister
G W
GW