TY - JOUR
T1 - Probing Peptidylprolyl Bond cis/trans Status Using Distal 19F NMR Reporters
AU - Killoran, Patrick M.
AU - Hanson, George S. M.
AU - Verhoork, Sanne J. M.
AU - Smith, Madeleine
AU - Del Gobbo, Davide
AU - Lian, Lu-Yun
AU - Coxon, Christopher R.
N1 - Funding Information:
We thank the UK Engineering and Physical Sciences Research Council (EPSRC) for funding this research through the postdoctoral appointments of P.M.K. and S.J.M.V. (EP/R020299/1). We also thank the University of Edinburgh for G.S.M.H.’s studentship. Finally, we thank Dr Dave Ellis (Heriot-Watt University) for providing invaluable technical assistance and advice.
Funding Information:
We thank the UK Engineering and Physical Sciences Research Council (EPSRC) for funding this research through the postdoctoral appointments of P.M.K. and S.J.M.V. (EP/R020299/1). We also thank the University of Edinburgh for G.S.M.H.’s studentship. Finally, we thank Dr Dave Ellis (Heriot‐Watt University) for providing invaluable technical assistance and advice.
Publisher Copyright:
© 2022 The Authors. Chemistry - A European Journal published by Wiley-VCH GmbH.
PY - 2023/3/16
Y1 - 2023/3/16
N2 - A method for measuring peptidylprolyl bond cis-trans conformational status in peptide models is described, using 4-fluorophenylalanine (4FPhe) as a distal reporter for 19F NMR. The %cis-Pro population was measured for peptides of the general structure Ac-X-Pro-Z-Ala-Ala-4FPhe (X and Z are proteinogenic amino acids) at pH 7.4, and provided conformational populations consistent with literature values obtained by more complex methods. This approach was applied to probe the prolyl bond status in pentapeptide models of the intrinsically disordered C-terminal region of α-synuclein, which mirrored the preferences in the Ac-X-Pro-Z-Ala-4FPhe models. Advantageously, the 19F reporter group does not need to be adjacent to or attached to proline to provide quantifiable signals and distal 4-fluorophenylalanines can be placed so as not to influence prolyl bond conformation. Finally, we demonstrated that the prolyl bond status is not significantly affected by pH when there are ionisable amino acid residues at the carboxyl side of proline, which makes 19F NMR an invaluable tool with which to study proline isomerism at a range of pHs and in different solvents and buffers.
AB - A method for measuring peptidylprolyl bond cis-trans conformational status in peptide models is described, using 4-fluorophenylalanine (4FPhe) as a distal reporter for 19F NMR. The %cis-Pro population was measured for peptides of the general structure Ac-X-Pro-Z-Ala-Ala-4FPhe (X and Z are proteinogenic amino acids) at pH 7.4, and provided conformational populations consistent with literature values obtained by more complex methods. This approach was applied to probe the prolyl bond status in pentapeptide models of the intrinsically disordered C-terminal region of α-synuclein, which mirrored the preferences in the Ac-X-Pro-Z-Ala-4FPhe models. Advantageously, the 19F reporter group does not need to be adjacent to or attached to proline to provide quantifiable signals and distal 4-fluorophenylalanines can be placed so as not to influence prolyl bond conformation. Finally, we demonstrated that the prolyl bond status is not significantly affected by pH when there are ionisable amino acid residues at the carboxyl side of proline, which makes 19F NMR an invaluable tool with which to study proline isomerism at a range of pHs and in different solvents and buffers.
KW - F NMR
KW - fluorinated amino acids
KW - peptides
KW - proline conformation
UR - http://www.scopus.com/inward/record.url?scp=85148090305&partnerID=8YFLogxK
U2 - 10.1002/chem.202203017
DO - 10.1002/chem.202203017
M3 - Article
C2 - 36550088
SN - 0947-6539
VL - 29
JO - Chemistry - A European Journal
JF - Chemistry - A European Journal
IS - 16
M1 - e202203017
ER -