Summary
2D 1H NMR spectroscopy of two α-helical peptides which differ in their amphipathicity has been used to investigate the relationships between amide-proton chemical shifts, amide-proton exchange rates, temperature, and trifluoroethanol (TFE) concentration. In 50% TFE, in which the peptides are maximally helical, the amide-proton chemical shift and temperature coefficient patterns are very similar to each other in each peptide. Temperature coefficients from −10 to −6 ppb/K, usually indicative of the lack of intramolecular hydrogen bonds, were observed even for hydrophobic amino acids in the center of the α-helices. However, slow hydrogen isotope exchange for residues from 4 to 16 in both 18-mer helices indicates intact intramolecular hydrogen bonds over most of the length of these peptides. Based on these anomalous observations, we suggest that the pattern of amide-proton shifts in α-helices in H2O/TFE solvents is dominated by bifurcated intermolecular hydrogen-bond formation between the backbone carbonyl groups and TFE. The amide-proton chemical shift changes with increasing temperature may be interpreted by a disruption of intermolecular hydrogen bonds between carbonyl groups and the TFE in TFE/water rather than by the length of intramolecular hydrogen bonds in α-helices.
References
AndersenN.H., ChenC.P., MarschnerT.M., KrystekJr.S.R. and BassolinoD.A. (1992) Biochemistry, 31, 1280–1295.
BlancoF.J., HerranzJ., GonzalezC., JimenezM.A., RicoM., SantoroJ. and NietoJ.L. (1992) J. Am. Chem. Soc., 114, 9676–9677.
BundiA. and WüthrichK. (1979a) Biopolymers, 18, 285–297.
BundiA. and WüthrichK. (1979b) Biopolymers, 18, 299–311.
DeDiosA.C., PearsonJ.G. and OldfieldE. (1993) Science, 260, 1491–1496.
DysonH.J., RanceM., HoughtenR.A., LernerR.A. and WrightP.E. (1988) J. Mol. Biol., 201, 161–200.
EisenbergD. (1984) Annu. Rev. Biochem., 53, 595–623.
GoodmanM., NaiderF. and TonioloC. (1971) Biopolymers, 10, 1719–1730.
JacksonM. and MantschH. (1992) Biochim. Biophys. Acta, 1118, 139–143.
JimenezM.A., NietoJ.L., RicoM., SantoroJ., HerranzJ. and BermejoF.J. (1986) J. Mol. Biol., 143, 435–438.
KesslerH. (1982) Angew. Chem., 94, 509–520.
KuntzI.D., KosenP.A. and CraigE.C. (1991) J. Am. Chem. Soc., 113, 1406–1408.
LlinásM. and KleinM.P. (1975) J. Am. Chem. Soc., 97, 4731–4737.
MerutkaG., DysonH.J. and WrightP.E. (1995) J. Biomol. NMR, 5, 14–24.
NelsonJ.W. and KallenbachN.R. (1989) Biochemistry, 28, 5256–5261.
ÖsapayK. and CaseD.A. (1991) J. Am. Chem. Soc., 113, 9436–9444.
PardiA., WagnerG. and WüthrichK. (1983) Eur. J. Biochem., 137, 445–454.
RothemundS., BeyermannM., KrauseE., KrauseG., BienertM., HodgesR.S., SykesB.D. and SönnichsenF.D. (1995) Biochemistry, 43, 12954–12962.
Rothemund, S., Krause, M., Beyermann, M., Bienert, M., Sykes, B.D. and Sönnichsen, F.D. (1996) Biopolymers, in press.
SönnichsenF.D., VanEykJ.E., HodgesR.S. and SykesB.D. (1992) Biochemistry, 31, 8790–8798.
UrryD.W. and LongM.M. (1976) CRC Crit. Rev. Biochem., 4, 1–45.
WagnerG., PardiA. and WüthrichK. (1983) J. Am. Chem. Soc., 105, 5948–5949.
WishartD.S., SykesB.D. and RichardsF.M. (1991) J. Mol. Biol., 222, 311–333.
WishartD.S., SykesB.D. and RichardsF.M. (1992) Biochemistry, 31, 1647–1651.
WishartD.S., BigamC.G., HolmA., HodgesR.S. and SykesB.D. (1995) J. Biomol. NMR, 5, 67–81.
ZhouN., ZhuB., SykesB.D. and HodgesR.S. (1992) J. Am. Chem. Soc., 114, 4320–4326.
Author information
Authors and Affiliations
Additional information
Supplementary Material is available upon request, comprising seven pages with listings of experimental details and the NMR shift data for the two peptides.
Electronic Supplementary Material
Rights and permissions
About this article
Cite this article
Rothemund, S., Weißhoff, H., Beyermann, M. et al. Temperature coefficients of amide proton NMR resonance frequencies in trifluoroethanol: A monitor of intramolecular hydrogen bonds in helical peptides?. J Biomol NMR 8, 93–97 (1996). https://doi.org/10.1007/BF00198143
Received:
Accepted:
Issue Date:
DOI: https://doi.org/10.1007/BF00198143