Quantitative determination of hydrocarbon chain conformational order in bilayers of saturated phosphatidylcholines of various chain lengths by Fourier transform infrared spectroscopy.

  title={Quantitative determination of hydrocarbon chain conformational order in bilayers of saturated phosphatidylcholines of various chain lengths by Fourier transform infrared spectroscopy.},
  author={H. Casal and R. McElhaney},
  volume={29 23},
The infrared spectra of aqueous dispersions of a homologous series of symmetric-chain, disaturated phosphatidylcholines, with fatty acyl chain lengths ranging from 12 to 19 carbons, have been measured at comparable reduced temperatures in their liquid-crystalline phases. The infrared spectra of these compounds contain bands that are dependent on the conformation of the fatty acyl chains. In particular, in the 1400-1300-cm-1 spectral region, there are bands due to CH2 wagging which are specific… Expand
FTIR studies of phospholipid membranes containing monoacetylenic acyl chains
The conformational behaviour of phosphatidylcholine and phosphatidyl acid membranes derived from octadec-14-ynoic and octadec-9-ynoic acid is studied by FTIR spectroscopy comprising both the liquidExpand
Abstract The conformational ordering of the acyl chains of all possible binary 1:1 mixtures containing the phospholipids DMPC, DMPA, DPPC, and DPPA was investigated using FTIR and 2H NMRExpand
Acyl chain conformational ordering in liquid-crystalline bilayers: comparative FT-IR and 2H-NMR studies of phospholipids differing in headgroup structure and chain length
AbstractFT-IR spectroscopy has been used to evaluate the acyl chain conformational ordering of DMPC, DMPE, DMPA (pH 6 and 12), DMPG (pH 1 and 7), and DPPC, DPPE, DPPA (pH 6). The frequencies of theExpand
Conformational disorder in unsaturated phospholipids by FTIR spectroscopy.
Conformational disorder in liquid alkenes and in the L alpha and Hparallel phases of some unsaturated phospholipids has been monitored by FTIR spectroscopy and difficulties in quantitative determination of conformational Disorder in unsaturated chains are discussed. Expand
Studies of highly asymmetric mixed-chain diacyl phosphatidylcholines that form mixed-interdigitated gel phases: Fourier transform infrared and 2H NMR spectroscopic studies of hydrocarbon chain conformation and orientational order in the liquid-crystalline state.
2H-NMR studies of the specifically chain-perdeuterated analogs of these asymmetric-chain lipids reveal that the orientational order parameter profiles of their shorter and longer chains differ both qualitatively and quantitatively, regardless of whether they are esterified at the sn1- or sn2 positions of the glycerol molecule. Expand
Conformation of phosphatidylcholine in neat and cholesterol-containing liquid-crystalline bilayers. Application of a novel method.
Analysis of the intramolecular pyrene-pyrene collision data obtained for 30 phosphatidylcholine species in terms of a simple geometrical model showed that addition of 50 mol % cholesterol had only a small effect on the penetration difference of the acyl chains, strongly suggesting that the conformation of phosphate in the liquid-crystalline state is determined largely by intramolescular, rather than intermolecular, interactions. Expand
Investigation of the Temperature Behavior of the Bands Due to the Methylene Stretching Vibrations of Phospholipid Acyl Chains by Two-Dimensional Infrared Correlation Spectroscopy
The temperature-induced gel-to-liquid crystalline phase transition of dipalmitoylphosphatidylcholine (DPPC) is characterized by a shift towards high frequencies and an increase of the width of theExpand
Temperature-Dependent Hydrocarbon Chain Disorder in Phosphatidylcholine Bilayers Studied by Raman Spectroscopy.
Temperature onset of the decrease of Raman intensity of the asymmetrical methylene stretching band is the same for unsaturated lipids (DLPC, POPC, and DOPC), which was interpreted as the importance of packing defects in the bilayers of these phospholipids. Expand
Quantitative IR studies of acyl chain conformational order in fatty acid homogeneous membranes of live cells of Acholeplasma laidlawii B.
Conformational order in the live cells and in the membranes was virtually identical over the range of cell viability, as measured by the thermotropic responses of the k = 1 and k = 2 components of the wagging mode progression. Expand
Infrared Spectroscopic Determination of Conformational Disorder and Microphase Separation in Phospholipid Acyl Chains
Infrared (IR) spectroscopy offers unique advantages for the study of phospholipid acyl chain structures and interactions. As is well known, the technique monitors molecular vibrations that produceExpand


Quantitative determination of conformational disorder in the acyl chains of phospholipid bilayers by infrared spectroscopy.
A method is proposed and demonstrated for the direct determination of conformational disorder (trans-gauche isomerization) as a function of acyl-chain position in phospholipid bilayer membranes with significant advantages of the FT-IR approach. Expand
A differential scanning calorimetric study of the thermotropic phase behavior of model membranes composed of phosphatidylcholines containing linear saturated fatty acyl chains.
The thermotropic phase behavior of a series of 1,2-diacylphosphatidylcholines containing linear saturated acyl chains of 10-22 carbons was studied by differential scanning calorimetry and indicated that the kinetic limitations become more severe as the length of the acyl chain increases. Expand
Lecithin bilayers. Density measurement and molecular interactions.
The consistency of these calculations supports the conclusion that the most important molecular energies for the main transition in lecithin bilayers are the hydrocarbon chain interactions and the rotational isomeric energies, and that the main phase transition is analogous to the melting transition in the alkanes from the hexagonal phase to the liquid phase, but with some modifications. Expand
Deuterium order parameters in relation to thermodynamic properties of a phospholiped bilayer. A statistical mechanical interpretation.
The physical properties of bilayers of dipalmitoyl-3-sn-phosphatidylcholine are analyzed in terms of a statistical model proposed by Marcelja, which yields the probabilities of trans and gauche conformations and also those of more specific conformational defects like kinks or jogs. Expand
Chain ordering in liquid crystals. II. Structure of bilayer membranes.
  • S. Marčelja
  • Chemistry, Biology
  • Biochimica et biophysica acta
  • 1974
The order parameter for hydrocarbon chains in bilayers (or monolayers) as a function of temperature, lateral pressure and position along the chain, is shown and compared with the available NMR data. Expand
Lipid conformation in model membranes and biological membranes.
Protein molecules in solution or in protein crystals are characterized by rather well-defined structures in which α-helical regions, β-pleated sheets, etc., are the key features. Likewise, the doubleExpand
Vibrational Study of the Chain Conformation of the Liquid n‐Paraffins and Molten Polyethylene
A vibrational and attendant conformational analysis of the liquid n‐paraffins and molten polyethylene is presented. For the purposes of the analysis a valence force field was derived which isExpand
Nonplanar Conformers and the Phase Behavior of Solid n- Alkanes
Solidsolid phase transitions of the odd n-alkanes n-C17H36 through n-C29H60 were studied by using differential scanning calorimetry (DSC) and infrared (IR) spectroscopy. Two phase transitions wereExpand
Fluorescence polarization studies of membrane fluidity: where do we go from here?
In the most general terms, the concept of membrane fluidity comprises a number of the motional characteristics of membrane components. It includes the translational and rotational motions of proteinsExpand
Conformation of the hydrocarbon chains of sodium dodecyl sulfate molecules in micelles: an FTIR study
Etude par spectrometrie IR de la conformation des hydrocarbures solubilises dans des micelles de dodecylsulfate de sodium