The diagonal anharmonicity of an amide I mode of protein backbones plays a critical role in a protein’s vibrational dynamics and energy transfer. However, this anharmonicity of long-chain peptides and proteins in H2O environment is still lacking. Here, we investigate the anharmonicity of the amide I band of proteins at the lipid membrane/H2O interface using a surface-sensitive pump–probe setup in which a femtosecond infrared pump is followed by a femtosecond broadband sum frequency generation vibrational spectroscopy probe. It is found that the anharmonicity of the amide I mode in ideal α-helical and β-sheet structures at hydrophobic environments is 3–4 cm−1, indicating that the amide I mode in ideal α-helical and β-sheet structures is delocalized over eight peptide bonds. The anharmonicity increases as the bandwidth of the amide I mode increases due to the exposure of peptide bonds to H2O. More H2O exposure amounts lead to a larger anharmonicity. The amide I mode of the peptides with large H2O exposure amounts is localized in one to two peptide bonds. Our finding reveals that the coupling between the amide I mode and the H2O bending mode does not facilitate the delocalization of the amide I mode along the peptide chain, highlighting the impact of H2O on energy transfer and structural dynamics of proteins.

1.
V.
Botan
,
E. H. G.
Backus
,
R.
Pfister
,
A.
Moretto
,
M.
Crisma
,
C.
Toniolo
,
P. H.
Nguyen
,
G.
Stock
, and
P.
Hamm
, “
Energy transport in peptide helices
,”
Proc. Natl. Acad. Sci. U. S. A.
104
,
12749
12754
(
2007
).
2.
K. A.
Dill
and
J. L.
MacCallum
, “
The protein-folding problem, 50 years on
,”
Science
338
,
1042
1046
(
2012
).
3.
Y.-C.
Chang
and
J. U.
Bowie
, “
Measuring membrane protein stability under native conditions
,”
Proc. Natl. Acad. Sci. U. S. A.
111
,
219
224
(
2014
).
4.
A.
Barth
and
C.
Zscherp
, “
What vibrations tell about proteins
,”
Q. Rev. Biophys.
35
,
369
430
(
2003
).
5.
L. K.
Tamm
and
S. A.
Tatulian
, “
Infrared spectroscopy of proteins and peptides in lipid bilayers
,”
Q. Rev. Biophys.
30
,
365
429
(
1997
).
6.
S.
Califano
,
Vibrational States
(
John Wiley & Sons
,
London, New York, Sydney, Toronto
,
1976
).
7.
K.
Cai
,
D.
Liu
,
C.
Lou
, and
S.
Lin
, “
Anharmonic vibrational probe for N-methylacetamide in different micro-environments
,”
Vib. Spectrosc.
66
,
8
13
(
2013
).
8.
A.
Roitberg
,
R. B.
Gerber
,
R.
Elber
, and
M. A.
Ratner
, “
Quantum self-consistent field calculations of BPTI
,”
Science
268
,
1319
1322
(
1995
).
9.
J.
Wang
,
J.
Chen
, and
R. M.
Hochstrasser
, “
Local structure of β-hairpin isotopomers by FTIR, 2D IR, and ab initio theory
,”
J. Phys. Chem. B
110
,
7545
7555
(
2006
).
10.
R. M.
Levy
,
D.
Perahia
, and
M.
Karplus
, “
Molecular dynamics of an α-helical polypeptide: Temperature dependence and deviation from harmonic behavior
,”
Proc. Natl. Acad. Sci. U. S. A.
79
,
1346
1350
(
1982
).
11.
D. M.
Leitner
, “
Anharmonic decay of vibrational states in helical peptides, coils, and one-dimensional glasses
,”
J. Phys. Chem. A
106
,
10870
10876
(
2002
).
12.
A. E.
Roitberg
,
R. B.
Gerber
, and
M. A.
Ratner
, “
A vibrational eigenfunction of a protein: Anharmonic coupled-mode ground and fundamental excited states of BPTI
,”
J. Phys. Chem. B
101
,
1700
1706
(
1997
).
13.
D. M.
Leitner
, “
Vibrational energy transfer in helices
,”
Phys. Rev. Lett.
87
,
188102
(
2001
).
14.
C. L.
Brooks
,
M.
Karplus
, and
B. M.
Pettitt
, “
Proteins: A theoretical perspective of dynamics, structure, and thermodynamics
,”
Adv. Chem. Phys.
71
,
1
(
1988
).
15.
P.
Hamm
,
M.
Lim
, and
R. M.
Hochstrasser
, “
Structure of the amide I band of peptides measured by femtosecond nonlinear-infrared spectroscopy
,”
J. Phys. Chem. B
102
,
6123
6138
(
1998
).
16.
J.
Wang
and
R. M.
Hochstrasser
, “
Anharmonicity of amide modes
,”
J. Phys. Chem. B
110
,
3798
3807
(
2006
).
17.
C.
Han
,
J.
Zhao
,
F.
Yang
, and
J.
Wang
, “
Structural dynamics of N-propionyl-D-glucosamine probed by infrared spectroscopies and ab initio computations
,”
J. Phys. Chem. A
117
,
6105
6115
(
2013
).
18.
S.
Bagchi
,
Y. S.
Kim
,
A. K.
Charnley
,
A. B.
Smith
, and
R. M.
Hochstrasser
, “
Two-dimensional infrared investigation of N-acetyl tryptophan methyl amide in solution
,”
J. Phys. Chem. B
111
,
3010
3018
(
2007
).
19.
M.
Lima
,
R.
Chelli
,
V. V.
Volkov
, and
R.
Righini
, “
Two-dimensional infrared spectroscopy of a structured liquid: Neat formamide
,”
J. Chem. Phys.
130
,
204518
(
2009
).
20.
I. V.
Rubtsov
,
J.
Wang
, and
R. M.
Hochstrasser
, “
Vibrational coupling between amide-I and amide-A modes revealed by femtosecond two color infrared spectroscopy
,”
J. Phys. Chem. A
107
,
3384
3396
(
2003
).
21.
S.
Sul
,
D.
Karaiskaj
,
Y.
Jiang
, and
N.-H.
Ge
, “
Conformations of N-acetyl-L-prolinamide by two-dimensional infrared spectroscopy
,”
J. Phys. Chem. B
110
,
19891
19905
(
2006
).
22.
M.
Candelaresi
,
E.
Ragnoni
,
C.
Cappelli
,
A.
Corozzi
,
M.
Lima
,
S.
Monti
,
B.
Mennucci
,
F.
Nuti
,
A. M.
Papini
, and
P.
Foggi
, “
Conformational analysis of Gly–Ala–NHMe in D2O and DMSO solutions: A two-dimensional infrared spectroscopy study
,”
J. Phys. Chem. B
117
,
14226
14237
(
2013
).
23.
Y. S.
Kim
and
R. M.
Hochstrasser
, “
Dynamics of amide-I modes of the alanine dipeptide in D2O
,”
J. Phys. Chem. B
109
,
6884
6891
(
2005
).
24.
J.
Zhao
and
J.
Wang
, “
Chain-length and mode-delocalization dependent amide-I anharmonicity in peptide oligomers
,”
J. Chem. Phys.
136
,
214112
(
2012
).
25.
O. F. A.
Larsen
,
P.
Bodis
,
W. J.
Buma
,
J. S.
Hannam
,
D. A.
Leigh
, and
S.
Woutersen
, “
Probing the structure of a rotaxane with two-dimensional infrared spectroscopy
,”
Proc. Natl. Acad. Sci. U. S. A.
102
,
13378
13382
(
2005
).
26.
P.
Bodis
,
R.
Timmer
,
S.
Yeremenko
,
W. J.
Buma
,
J. S.
Hannam
,
D. A.
Leigh
, and
S.
Woutersen
, “
Heterovibrational interactions, cooperative hydrogen bonding, and vibrational energy relaxation pathways in a rotaxane
,”
J. Phys. Chem. C
111
,
6798
6804
(
2007
).
27.
P.
Hamm
,
M.
Lim
,
W. F.
DeGrado
, and
R. M.
Hochstrasser
, “
The two-dimensional IR nonlinear spectroscopy of a cyclic penta-peptide in relation to its three-dimensional structure
,”
Proc. Natl. Acad. Sci. U. S. A.
96
,
2036
2041
(
1999
).
28.
C. H.
Londergan
,
J.
Wang
,
P. H.
Axelsen
, and
R. M.
Hochstrasser
, “
Two-dimensional infrared spectroscopy displays signatures of structural ordering in peptide aggregates
,”
Biophys. J.
90
,
4672
4685
(
2006
).
29.
C.
Fang
,
J.
Wang
,
A. K.
Charnley
,
W.
Barber-Armstrong
,
A. B.
Smith
 III
,
S. M.
Decatur
, and
R. M.
Hochstrasser
, “
Two-dimensional infrared measurements of the coupling between amide modes of an α-helix
,”
Chem. Phys. Lett.
382
,
586
592
(
2003
).
30.
C.
Fang
,
A.
Senes
,
L.
Cristian
,
W. F.
DeGrado
, and
R. M.
Hochstrasser
, “
Amide vibrations are delocalized across the hydrophobic interface of a transmembrane helix dimer
,”
Proc. Natl. Acad. Sci. U. S. A.
103
,
16740
16745
(
2006
).
31.
S.
Bagchi
,
C.
Falvo
,
S.
Mukamel
, and
R. M.
Hochstrasser
, “
2D-IR experiments and simulations of the coupling between amide-I and ionizable side chains in proteins: Application to the villin headpiece
,”
J. Phys. Chem. B
113
,
11260
11273
(
2009
).
32.
Y. L.
Ling
,
D. B.
Strasfeld
,
S.-H.
Shim
,
D. P.
Raleigh
, and
M. T.
Zanni
, “
Two-dimensional infrared spectroscopy provides evidence of an intermediate in the membrane-catalyzed assembly of diabetic amyloid
,”
J. Phys. Chem. B
,
113
2498
2505
(
2009
).
33.
D. B.
Strasfeld
,
Y. L.
Ling
,
R.
Gupta
,
D. P.
Raleigh
, and
M. T.
Zanni
, “
Strategies for extracting structural information from 2D IR spectroscopy of amyloid: Application to islet amyloid polypeptide
,”
J. Phys. Chem. B
113
,
15679
15691
(
2009
).
34.
K. A.
Peterson
,
C. W.
Rella
,
J. R.
Engholm
, and
H. A.
Schwettman
, “
Ultrafast vibrational dynamics of the myoglobin amide I band
,”
J. Phys. Chem. B
103
,
557
561
(
1999
).
35.
R.
Schweitzer-Stenner
, “
Dihedral angles of tripeptides in solution directly determined by polarized Raman and FTIR spectroscopy
,”
Biophys. J.
83
,
523
532
(
2002
).
36.
C.-J.
Feng
and
A.
Tokmakoff
, “
The dynamics of peptide-water interactions in dialanine: An ultrafast amide I 2D IR and computational spectroscopy study
,”
J. Chem. Phys.
147
,
085101
(
2017
).
37.
J.
Yang
,
Y.
Wang
,
L.
Wang
, and
D.
Zhong
, “
Mapping hydration dynamics around a β-barrel protein
,”
J. Am. Chem. Soc.
139
,
4399
4408
(
2017
).
38.
D.
Laage
,
T.
Elsaesser
, and
J. T.
Hynes
, “
Water dynamics in the hydration shells of biomolecules
,”
Chem. Rev.
117
,
10694
10725
(
2017
).
39.
J.
Tan
,
J.
Zhang
,
C.
Li
,
Y.
Luo
, and
S.
Ye
, “
Ultrafast energy relaxation dynamics of amide I vibrations coupled with protein-bound water molecules
,”
Nat. Commun.
10
,
1010
(
2019
).
40.
A.
Ghosh
and
R. M.
Hochstrasser
, “
A peptide’s perspective of water dynamics
,”
Chem. Phys.
390
,
1
13
(
2011
).
41.
P.
Hamm
,
M.
Lim
,
W. F.
DeGrado
, and
R. M.
Hochstrasser
, “
Pump/probe self heterodyned 2D spectroscopy of vibrational transitions of a small globular peptide
,”
J. Chem. Phys.
112
,
1907
1916
(
2000
).
42.
P.
Mukherjee
,
I.
Kass
,
I. T.
Arkin
, and
M. T.
Zanni
, “
Picosecond dynamics of a membrane protein revealed by 2D IR
,”
Proc. Natl. Acad. Sci. U. S. A.
103
,
3528
3533
(
2006
).
43.
Y. R.
Shen
,
The Principles of Nonlinear Optics
(
Wiley
,
New York
,
1984
).
44.
A. G.
Lambert
,
P. B.
Davies
, and
D. J.
Neivandt
, “
Implementing the theory of sum frequency generation vibrational spectroscopy: A tutorial review
,”
Appl. Spectrosc. Rev.
40
,
103
145
(
2005
).
45.
E. C. Y.
Yan
,
L.
Fu
,
Z.
Wang
, and
W.
Liu
, “
Biological macromolecules at interfaces probed by chiral vibrational sum frequency generation spectroscopy
,”
Chem. Rev.
114
,
8471
8498
(
2014
).
46.
B.
Ding
,
J.
Jasensky
,
Y.
Li
, and
Z.
Chen
, “
Engineering and characterization of peptides and proteins at surfaces and interfaces: A case study in surface-sensitive vibrational spectroscopy
,”
Acc. Chem. Res.
49
,
1149
1157
(
2016
).
47.
D. K.
Schach
,
W.
Rock
,
J.
Franz
,
M.
Bonn
,
S. H.
Parekh
, and
T.
Weidner
, “
Reversible activation of a cell-penetrating peptide in a membrane environment
,”
J. Am. Chem. Soc.
137
,
12199
12202
(
2015
).
48.
S.
Ye
,
H.
Li
,
W.
Yang
, and
Y.
Luo
, “
Accurate determination of interfacial protein secondary structure by combining interfacial-sensitive amide I and amide III spectral signals
,”
J. Am. Chem. Soc.
136
,
1206
1209
(
2014
).
49.
W.
Guo
,
T.
Lu
,
Z.
Gandhi
, and
Z.
Chen
, “
Probing orientations and conformations of peptides and proteins at buried interfaces
,”
J. Phys. Chem. Lett.
12
,
10144
10155
(
2021
).
50.
A.
Perry
,
H.
Ahlborn
,
B.
Space
, and
P. B.
Moore
, “
A combined time correlation function and instantaneous normal mode study of the sum frequency generation spectroscopy of the water/vapor interface
,”
J. Chem. Phys.
118
,
8411
8419
(
2003
).
51.
K.
Engelhardt
,
W.
Peukert
, and
B.
Braunschweig
, “
Vibrational sum-frequency generation at protein modified air–water interfaces: Effects of molecular structure and surface charging
,”
Curr. Opin. Colloid Interface Sci.
19
,
207
215
(
2014
).
52.
J.
Wang
,
M. A.
Even
,
X.
Chen
,
A. H.
Schmaier
,
J. H.
Waite
, and
Z.
Chen
, “
Detection of amide I signals of interfacial proteins in situ using SFG
,”
J. Am. Chem. Soc.
125
,
9914
9915
(
2003
).
53.
K.
Meister
,
S. J.
Roeters
,
A.
Paananen
,
S.
Woutersen
,
J.
Versluis
,
G. R.
Szilvay
, and
H. J.
Bakker
, “
Observation of pH-induced protein reorientation at the water surface
,”
J. Phys. Chem. Lett.
8
,
1772
1776
(
2017
).
54.
B.
Ding
,
A.
Panahi
,
J.-J.
Ho
,
J. E.
Laaser
,
C. L.
Brooks
,
M. T.
Zanni
, and
Z.
Chen
, “
Probing site-specific structural information of peptides at model membrane interface in situ
,”
J. Am. Chem. Soc.
137
,
10190
10198
(
2015
).
55.
J. A.
McGuire
and
Y. R.
Shen
, “
Ultrafast vibrational dynamics at water interfaces
,”
Science
313
,
1945
1948
(
2006
).
56.
C.-S.
Hsieh
,
R. K.
Campen
,
M.
Okuno
,
E. H. G.
Backus
,
Y.
Nagata
, and
M.
Bonn
, “
Mechanism of vibrational energy dissipation of free OH groups at the air–water interface
,”
Proc. Natl. Acad. Sci. U. S. A.
110
,
18780
18785
(
2013
).
57.
S.
Nihonyanagi
,
S.
Yamaguchi
, and
T.
Tahara
, “
Ultrafast dynamics at water interfaces studied by vibrational sum frequency generation spectroscopy
,”
Chem. Rev.
117
,
10665
10693
(
2017
).
58.
E. H. G.
Backus
,
J.
Schaefer
, and
M.
Bonn
, “
Probing the mineral–water interface with nonlinear optical spectroscopy
,”
Angew. Chem., Int. Ed.
60
,
10482
(
2021
).
59.
A.
Eftekhari-Bafrooei
and
E.
Borguet
, “
Effect of surface charge on the vibrational dynamics of interfacial water
,”
J. Am. Chem. Soc.
131
,
12034
12035
(
2009
).
60.
S. T.
van der Post
,
C.-S.
Hsieh
,
M.
Okuno
,
Y.
Nagata
,
H. J.
Bakker
,
M.
Bonn
, and
J.
Hunger
, “
Strong frequency dependence of vibrational relaxation in bulk and surface water reveals sub-picosecond structural heterogeneity
,”
Nat. Commun.
6
,
8384
(
2015
).
61.
A.
Tuladhar
,
S.
Dewan
,
S.
Pezzotti
,
F. S.
Brigiano
,
F.
Creazzo
,
M.-P.
Gaigeot
, and
E.
Borguet
, “
Ions tune interfacial water structure and modulate hydrophobic interactions at silica surfaces
,”
J. Am. Chem. Soc.
142
,
6991
7000
(
2020
).
62.
A.
Eftekhari-Bafrooei
and
E.
Borguet
, “
Effect of electric fields on the ultrafast vibrational relaxation of water at a charged solid–liquid interface as probed by vibrational sum frequency generation
,”
J. Phys. Chem. Lett.
2
,
1353
1358
(
2011
).
63.
M.
Smits
,
A.
Ghosh
,
M.
Sterrer
,
M.
Müller
, and
M.
Bonn
, “
Ultrafast vibrational energy transfer between surface and bulk water at the air-water interface
,”
Phys. Rev. Lett.
98
,
098302
(
2007
).
64.
A.
Ghosh
,
M.
Smits
,
J.
Bredenbeck
, and
M.
Bonn
, “
Membrane-bound water is energetically decoupled from nearby bulk water: An ultrafast surface-specific investigation
,”
J. Am. Chem. Soc.
129
,
9608
9609
(
2007
).
65.
M.
Bonn
,
H. J.
Bakker
,
A.
Ghosh
,
S.
Yamamoto
,
M.
Sovago
, and
R. K.
Campen
, “
Structural inhomogeneity of interfacial water at lipid monolayers revealed by surface-specific vibrational pump−probe spectroscopy
,”
J. Am. Chem. Soc.
132
,
14971
14978
(
2010
).
66.
J.
Tan
,
B.
Zhang
,
Y.
Luo
, and
S.
Ye
, “
Ultrafast vibrational dynamics of membrane-bound peptides at the lipid bilayer/water interface
,”
Angew. Chem., Int. Ed.
56
,
12977
12981
(
2017
).
67.
J.
Zhang
,
J.
Tan
,
R.
Pei
,
S.
Ye
, and
Y.
Luo
, “
Ordered water layer on the macroscopically hydrophobic fluorinated polymer surface and its ultrafast vibrational dynamics
,”
J. Am. Chem. Soc.
143
,
13074
13081
(
2021
).
68.
X.
Hu
,
J.
Tan
, and
S.
Ye
, “
Reversible activation of pH-responsive cell-penetrating peptides in model cell membrane relies on the nature of lipid
,”
J. Phys. Chem. C
121
,
15181
15187
(
2017
).
69.
Y.
Liu
,
J.
Tan
,
J.
Zhang
,
C.
Li
,
Y.
Luo
, and
S.
Ye
, “
Influenza A M2 transmembrane domain tunes its conformational heterogeneity and structural plasticity in the lipid bilayer by forming loop structures
,”
Chem. Commun.
54
,
5903
5906
(
2018
).
70.
B.
Zhang
,
J.
Tan
,
C.
Li
,
J.
Zhang
, and
S.
Ye
, “
Amide I SFG spectral line width probes the lipid–peptide and peptide–peptide interactions at cell membrane in situ and in real time
,”
Langmuir
34
,
7554
7560
(
2018
).
71.
W.
Wang
,
J.
Tan
, and
S.
Ye
, “
Unsaturated lipid accelerates formation of oligomeric β-sheet structure of GP41 fusion peptide in model cell membrane
,”
J. Phys. Chem. B
124
,
5169
5176
(
2020
).
72.
S. K.
Kandasamy
and
R. G.
Larson
, “
Molecular dynamics simulations of model trans-membrane peptides in lipid bilayers: A systematic investigation of hydrophobic mismatch
,”
Biophys. J.
90
,
2326
2343
(
2006
).
73.
J.
Tan
,
Y.
Luo
, and
S.
Ye
, “
A highly sensitive femtosecond time-resolved sum frequency generation vibrational spectroscopy system with simultaneous measurement of multiple polarization combinations
,”
Chin. J. Chem. Phys.
30
,
671
677
(
2017
).
74.
D.
Xiao
,
L.
Fu
,
J.
Liu
,
V. S.
Batista
, and
C. Y. E.
Yan
, “
Amphiphilic adsorption of human islet amyloid polypeptide aggregates to lipid/aqueous interfaces
,”
J. Mol. Biol.
421
,
537
547
(
2012
).
75.
P.
Guyot-Sionnest
, “
Two-phonon bound state for the hydrogen vibration on the H/Si(111) surface
,”
Phys. Rev. Lett.
67
,
2323
2326
(
1991
).
76.
S. H.
Schneider
,
H. T.
Kratochvil
,
M. T.
Zanni
, and
S. G.
Boxer
, “
Solvent-independent anharmonicity for carbonyl oscillators
,”
J. Phys. Chem. B
121
,
2331
2338
(
2017
).
77.
I. V.
Rubtsov
and
R. M.
Hochstrasser
, “
Vibrational dynamics, mode coupling, and structural constraints for acetylproline-NH2
,”
J. Phys. Chem. B
106
,
9165
9171
(
2002
).
78.
C.
Falvo
,
T.
Hayashi
,
W.
Zhuang
, and
S.
Mukamel
, “
Coherent two dimensional infrared spectroscopy of a cyclic decapeptide antamanide. A simulation study of the amide-I and A bands
,”
J. Phys. Chem. B
112
,
12479
12490
(
2008
).
79.
J. E.
Laaser
,
D. R.
Skoff
,
J.-J.
Ho
,
Y.
Joo
,
A. L.
Serrano
,
J. D.
Steinkruger
,
P.
Gopalan
,
S. H.
Gellman
, and
M. T.
Zanni
, “
Two-dimensional sum-frequency generation reveals structure and dynamics of a surface-bound peptide
,”
J. Am. Chem. Soc.
136
,
956
962
(
2014
).
80.
A.
Okada
,
K.
Wakamatsu
,
T.
Miyazawa
, and
T.
Higashijima
, “
Vesicle-bound conformation of melittin: Transferred nuclear overhauser enhancement analysis in the presence of perdeuterated phosphatidylcholine vesicles
,”
Biochemistry
33
,
9438
9446
(
1994
).
81.
A. L.
Stouffer
,
R.
Acharya
,
D.
Salom
,
A. S.
Levine
,
L.
Di Costanzo
,
C. S.
Soto
,
V.
Tereshko
,
V.
Nanda
,
S.
Stayrook
, and
W. F.
DeGrado
, “
Structural basis for the function and inhibition of an influenza virus proton channel
,”
Nature
451
,
596
599
(
2008
).
82.
L.
Piatkowski
and
H. J.
Bakker
, “
Vibrational dynamics of the bending mode of water interacting with ions
,”
J. Chem. Phys.
135
,
214509
(
2011
).
83.
O. F. A.
Larsen
and
S.
Woutersen
, “
Vibrational relaxation of the H2O bending mode in liquid water
,”
J. Chem. Phys.
121
,
12143
12145
(
2004
).

Supplementary Material

You do not currently have access to this content.