Abstract
In polarized infrared (IR) absorption experiments, dichroic values are used to study the structure and orientation of lipid molecules. From computer simulations, we obtained angular distributions of IR transition moment (TM) orientations of the stretch vibrations of CH2 groups of 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphatidylcholin (POPC) lipid bilayers in the gel (L β) and fluid (L α) phases. From these distributions, we calculated dichroic absorption values, as well as order parameters. We established a connection between the dichroic ratio R ATR, which is measured in IR-ATR setups, with the dichroic ratio D and the order parameter S zz . The calculated values compare well with experimental results for the fluid phase. In addition, we computed angular distributions of transition moments with respect to the tail director orientation for the gel and the fluid phases. Only small differences were found between the distributions in the symmetric stretch orientation, the asymmetric stretch orientation, and the C-H bond orientation of CH2 groups. The distributions of tail directors of POPC showed average tilts of 14.7° in the gel phase and 32.9° in the fluid phase. We developed a theory which makes it possible to calculate average tilt angles of tail directors in the gel phase from dichroic absorption values obtained from IR measurements for a wide range of lipids. Legendre coefficients were calculated from TM distributions. Order parameters, defined as the second Legendre polynomial, were found to closely approximate the TM distribution in lipid bilayers in the fluid phase.
This is a preview of subscription content, log in via an institution to check access.
Similar content being viewed by others
Abbreviations
- MD:
-
molecular dynamics
- IR:
-
infrared
- ATR:
-
attenuated total reflection
- TM:
-
transition moment
- POPC:
-
1-palmitoyl-2-oleoyl-sn-glycero-3-phosphatidyl-cholin
- POPG:
-
1-palmitoyl-2-oleoyl-sn-glycero-3-phos-phatidylglycerol
- DPPC:
-
1,2-dipalmitoyl-sn-glycero-3-phosphatidylcholin
- NMR:
-
nuclear magnetic resonance
References
Banko B, Heller H (1991) User Manual for EGO- Release 1.1. Beckman Institute Technical Report TB-92-07
Bayerl TM, Schmidt CF, Sackmann E (1988) Kinetics of symmetric and asymmetric phospholipid transfer between small sonicated vesicles studied by high-sensitivity differential scanning calorimetry, NMR, electron microscopy, and dynamic light scattering. Biochemistry 27:6078–6085
Bellamy LJ (1975) The infrared spectra of complex molecules. Methuen, London
Bolterauer C (1996) The IR order parameter and the order tensor. Eur Biophys J (in press)
Brauner JW, Mendelsohn R, Prendergast FG (1987) Attenuated total reflectance fourier transform infrared studies of the interaction of melittin, two fragments of melittin, and δ-hemoysin with phosphatidylcholines. Biochemistry 26:8151–8158
Brooks BR, Bruccoleri RE, Olafson BD, States DJ, Swaminathan S, Karplus M (1983) CHARMM: a program for macromolecular energy, minimization, and dynamics calculations. J Comp Chem 4:187–217
Brünger AT (1988) X-PLOR. The Howard Hughes Medical Institute and Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT
Brünger AT (1990) X-PLOR, Version 2.1. The Howard Hughes Medical Institute and Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT
Chandrasekhar S (1992) Liquid crystals. Cambridge University Press, Cambridge
Chia NC, Mendelsohn R (1992) CH2 wagging modes of unsaturated acyl chains as IR probes of conformational order in methyl alkenoates and phospholipid bilayers. J Phys Chem 96:10543–10547
Damodaran KV, Merz Jr KM, Gaber BP (1992) Structure and dynamics of the dilauroylphosphatidylethanolamine lipid bilayer. Biochemistry 31:7656–7664
Egger M, Ohnesorge F, Weisenhorn AL, Heyn SP, Drake B, Prater CB, Gould SAC, Hansma PK, Gaub HE (1990) Wet lipid-protein membranes imaged at submolecular resolution by atomic force microscopy. J Struct Biol 103:89–94
Frey S, Tamm LK (1991) Orientation of melittin in phospholipid bilayers. Biophys J 60:922–930
Fringeli UP, Gunthard HH (1981) Infrared membrane spectroscopy. In: E Grell (ed) Membrane spectroscopy. Springer, Berlin Heidelberg New York, pp 270–332
Goldstein H (1989) Classical mechanics. Addison-Wesley
Grubmuller H, Heller H, Windemuth A, Schulten K (1991) Generalized Verlet algorithm for efficient molecular dynamics simulations with long-range interactions. Mol Simulation 6:121–142
Harrick NJ, Pre FKD (1966) Appl Optics 5: 1739–1743
He K, Ludtke SJ, Huang HW, Andersen O, Greathouse D, II REK (1994) Closed state of gramicidin channel detected by X-ray inplane scattering. Biophys Chem 49:83–89
Heitler W (1954) The Quantum theory of radiation. V. Oxford University Press, Oxford
Heller H, Grubmuller H, Schulten K (1990) Molecular dynamics simulation on a parallel computer. Mol Simulation 5:133–165
Heller H, Schaefer M, Schulten K (1993) Molecular dynamics simulation of a bilayer of 200 lipids in the gel and in the liquid crystal phases. J Phys Chem 97:8343–8360
Heller H (1988) Diploma thesis, Technical University of Munich, Germany
Heller H (1993) Simulation einer Lipidmembran auf einem Parallelrechner. Doctoral dissertation, Technical University of Munich, Germany
Hübner W, Mantsch HH (1991) Orientation of specifically 13C-O labeled phosphatidylcholine multilayers from polarized attenuated total reflection FT-IR spectroscopy. Biophys 159:1261–1272
König S, Pfeiffer W, Bayerl T, Richter D, Sackmann E (1992) Molecular dynamics of lipid bilayers studied by incoherent quasielastic neutron scattering. J Phys II France 2:1589–1615
Kubo R (1969) Adv Chem Phys 15:101
Ludtke S (1993) MolViewer, Version 0.92β. Physics Dept, Rice University, Houston TX
Maier W, Saupe A (1958) Z Naturforsch 13a:564
Raine ARC (1990) Molecular dynamics simulation of proteins on an array of transputers. In: Pritchard DJ, Scott CJ (eds) Appl transputers 2, Proceedings of the Second International Conference on Applications of Transputers. Amsterdam, Netherlands, IOS Press, pp 272–279
Ryckaert J-P, Ciccotti G, Berendsen HJC (1977) Numerical integration of the cartesian equations of motion of a system with constraints: Molecular dynamics of n-alkanes. J Comp Phys 23:327–341
Schachtenschneider JH, Snyder RG (1962) Vibrational analysis of the n-paraffins-ii. normal co-ordinate calculation. Spectrochim Acta 19:117–168
Seelig J, Macdonald PM (1987) Phospholipids and proteins in biological membranes. 2H NMR as a method to study structure, dynamics and interactions. Ace Chem Res 20:221–228
Seelig J, Seelig A (1980) Lipid conformation in model membranes and biological membranes. Quart Rev Biophys 13:19–61
Seelig J (1977) Deuterium magnetic resonance: theory and application to lipid membranes. Quart Rev Biophys 10:353–418
Sinha AB, Schulten K, Heller H (1994) Performance analysis of a parallel molecular dynamics program. Comput Phys Commun 78:265–278
Small DM (1986) The physical chemistry of lipids. Plenum Publishing Corp, New York
Snyder RG, Schachtenschneider JH (1963) Vibrational analysis of n-paraffins-i. Spectrochim Acta 19:85–117
Tuchtenhagen J, Ziegler W, Blume A (1994) Acyl chain conformational ordering in liquid-crystalline bilayers: comparative FT-IR and 2H-NMR studies of phospolipids differing in head-group structure and chain length. Eur Biophys J 23:323–335
Verlet L (1967) Computer “experiments” on classical fluids. I. Thermodynamical properties of Lennard-Jones molecules. Phys Rev 159:98–103
Wesemann M (1994) SciPlot, Version 3.99. Berlin, Germany
Zaccai G, Büldt G, Seelig A, Seelig J (1979) Neutron diffraction studies on phosphatidylcholine model membranes. II. chain conformation and segmental disorder. J Mol Biol 134:693–706
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Bolterauer, C., Heller, H. Calculation of IR dichroic values and order parameters from molecular dynamics simulations and their application to structure determination of lipid bilayers. Eur Biophys J 24, 322–334 (1996). https://doi.org/10.1007/BF00180373
Received:
Accepted:
Issue Date:
DOI: https://doi.org/10.1007/BF00180373