Code: ThP25	Time Slot/Poster Number: 041	Session: Molecular Biophysics and Photobiology II
Raman and DFT Investigations of Glycine + (Water)n=1-5 Clusters
Animesh Ojha; Animesh Ojha
Motilal Nehru National Institute of Technology, Allahabad, India
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Summary
A cmbined Raman and DFT investigations of Glycine + (water)n=1-5 clusters have been done. The theoretically simulated Raman spectra corresponding to most stable conformer of [ZGly + (W)5] with BE -22.8 kcal/mol are matching nicely with the experimentally observed Raman spectra. Thus we conclude that the conformer, [ZGly + (W)5] is most probable hydrogen bonded complexes of glycine with water molecules. The spectroscopic observation demonstrates that the five water molecules are needed to stabilize the zwitterionic form of the glycine in aqueous medium.

Code: ThP25	Time Slot/Poster Number: 042	Session: Molecular Biophysics and Photobiology II
Direct Observations of Low Frequency Vibrational Coherences in wt-GFP
Arthur Mcclelland1; Alexander Demidov1; Abdelkrim Benabbas1; Yuhan Sun1; Karunakaran Venugopal1; Timothy Sage1; Jasper van Thor2; Paul Champion1
1Northeastern University, Boston, MA; 2Imperial College, London, UK
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Summary
Green Fluorescent Protein (GFP) from the jellyfish Aequorea Victoria is unique in showing Excited State Proton Transfer (ESPT) in a protein environment. Recently there has been increased interest in low frequency modes of GFP as they are thought to be important in explaining the chromophore-protein interactions. We present exciting new experimental observations of low frequency vibrational coherences in the ESPT coordinate both at room temperature and low temperature and our progress in understanding the implications.

Code: ThP25	Time Slot/Poster Number: 043	Session: Molecular Biophysics and Photobiology II
Raman And Infrared Spectra Of Hydrated 5-Nitrouracil Molecule
V.K. Rastogi; Alcolea Palafox; A. Guerrero-Martínez; G. Tardajos; Padam Kumar; Hitesh Kumar
Professor, Madrid, Spain
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Summary
5-Nitrouracil is currently of prime interest to the biological and pharmaceutical sciences. Thus, a theoretical and experimental study of this molecule was carried out. The calculations were carried out by using B3LYP/6-31G** implemented in the GAUSSIAN 03 program package. The molecule was considered in the isolated state as well as in the hydrated form with a variable number of explicit water molecules until ten. The simulated IR and Raman spectra were scaled and compared with the experimental ones. The influence of the water on the spectra was discussed.

Code: ThP25	Time Slot/Poster Number: 044	Session: Molecular Biophysics and Photobiology II
Transformation of Raman Spectra of 6-azacytidine and related compounds under deuteration
Marianna Iakhnenko
Department of Physics, Taras Shevchenko National U, Kyiv, Ukraine
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Summary
Measured Raman spectra of anomalous nucleoside 6-azacytidine and related compounds in H2O and D2O solutions show shifts of some peaks of the said compounds dissolved in D2O to high frequencies in contrast to their position in H2O solution. Calculation of such Raman spectra for different hypothetic hydrogen isotopes (atomic mass in range 1≤mH≤2) were made in order to explain such shifts. We assume that transformation of Raman spectra is not connected with increasing of mode frequency due to deuteration of nucleoside molecule, but with changing of relative intensities of Raman peaks corresponding to the pair of adjacent vibrational modes.

Code: ThP25	Time Slot/Poster Number: 045	Session: Molecular Biophysics and Photobiology II
High Pressure Raman Spectroscopy with a Micro-Capillary Cell
SangHoon Park; Thomas Oakeson; Alfons Schulte
University of Central Florida, Orlando, FL
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Summary
We describe a setup which combines a Raman microscope and a novel high pressure cell. A micro-capillary made out of fused silica simultaneously serves as the supporting body and the optical window of the high pressure cell. We present experiments over the pressure range from atmospheric pressure to 4 kBar in a micro-capillary that use less than 100 nanoliters of sample. We investigate pressure dependent structural changes in DMPC lipid systems through measurements of the Raman spectrum in the CH2 stretch band and fingerprint regions.

Code: ThP25	Time Slot/Poster Number: 046	Session: Molecular Biophysics and Photobiology II
Brillouin Scattering in Lysozyme Solutions
Augustinus Asenbaum1; Christian Pruner1; Emmerich Wilhelm1; Anna Svanidze2; Sergey Lushnikov 2; Alfons Schulte3
1Experimental Physics, University of Salzburg, Salzburg, AUSTRIA; 2A. F. Ioffe Physical Technical Institute, St. Petersburg, Russia; 3University of Central Florida, Orlando, Florida
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Summary
We investigate the Brillouin spectrum of lysozyme solutions from 275 K to 335 K and compare to the spectrum of water. A six-pass tandem Fabry-Perot interferometer is used in both 90° and 180° geometries. Ultrasonic speed measurements at 3 MHz are also reported. The lysozyme concentrations are 200 mg/ml and 250 mg/ml, respectively. For the lysozyme solution, the observed higher values of the sound speed at GHz frequencies, as measured by Brillouin scattering, could indicate additional relaxation processes as compared to pure bulk water, where no sound dispersion between ultrasonic speed and hypersonic speed is observed.

Code: ThP25	Time Slot/Poster Number: 047	Session: Molecular Biophysics and Photobiology II
Optical Trapping Raman Spectroscopy Of Protein and Membrane Interaction
Anjan Roy; Marcelo Nakaema; Timothy Keiderling
University of Illinois - Chicago, Chicago, IL
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Summary
We use optical trapping and Raman scattering to investigate the interactions between proteins and the membranes of individual vesicles. We propose to add the capability of mechanical force measurement into a single beam optical tweezers coupled to a Raman microscope. The optical trap serves as a handle to control the interaction of the membrane and peptide and it ensures the analyte is trapped in the focal volume of the laser so that we can collect spectra of extremely dilute systems. Force measurements allow us to correlate conformational changes and binding energetics.

Code: ThP25	Time Slot/Poster Number: 048	Session: Molecular Biophysics and Photobiology II
Conformational Vibrations of DNA with Counterions in the Low-Frequency Raman Spectra
Sergiy Volkov; Sergiy Perepelytsya
Bogolyubov Institute for Theoretical Physics, Kiev, Ukraine
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Summary
The goal of the present work is to describe the conformational vibrations of DNA with counterions and to determine the specific ion-phosphate modes in DNA low-frequency Raman spectra. The conformational vibrations of DNA with counterions are studied in framework of phenomenological model considering the vibrations of double helix structural elements and alkali metal ions tethered to DNA backbone phosphates. The calculations and comparison with experimental data prove our suggestion about existence of ion-phosphate vibrations in the DNA low-frequency spectra. The results show the dependence of DNA ion-phosphate modes on counterion type.

Code: ThP25	Time Slot/Poster Number: 049	Session: Molecular Biophysics and Photobiology II
Raman spectroscopy reveals the structure-fluidity interplay of model lipid membranes under oxidative stress
Ian Liau
National Chiao Tung University, Hsinchu, Taiwan
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Summary
We report the employment of Raman spectroscopy and fluorescence correlation spectroscopy to characterize model lipid membranes under oxidative stress. We showed that hydroxyl radical caused a significant increase of membrane fluidity and rationalized the result with the diminished Raman intensities associated with –CH2 and C=C moieties in lipids. The same approach also accounted the anti-oxidation capability of vitamin C and vitamin E and a novel inhibitory effect of cholesterol bound to a membrane against the change of its fluidity induced by oxidation.

Code: ThP25	Time Slot/Poster Number: 050	Session: Molecular Biophysics and Photobiology II
Quantum Mechanical Studies, Molecular Structures and Vibrational Characteristics of the Amino Acid (L-VALINE)
Manoj Kumar
Banaras Hindu University, Varanasi, India
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Summary
FT-Raman spectrum of the L-VALINE have been recorded and analyzed in the range 50-4000 cm-1. The stabilities, optimized molecular geometries, APT charges and vibrational characteristics for the L-Valine amino acid have been studied density functional theory (DFT) method with b3lyp/6-311++g** basis set. L-Valine is essential amino acid is classified as non-polar. Human dietary sources include cottage cheese, fish, poultry, peanuts, sesame seeds, and lentils. It is named after the plant valerian. In sickle-cell disease, valine substitutes for the hydrophilic amino acid glutamic acid in hemoglobin. Because valine is hydrophobic, the hemoglobin does not fold correctly.

Code: ThP25	Time Slot/Poster Number: 051	Session: Molecular Biophysics and Photobiology II
FT-IR and FT-Raman Spectra of 2, 6-Difluorobenzonitrile
J.K. Vats; S. Soam; Alcolea Palafox; P. Arora; H.P. Mital; V.K. Rastogi
Professor, Madrid, Spain
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Summary
From the spectroscopy point of view the vibrational spectra of benzonitrile and mono- and di- substituted benzonitriles have been extensively studied. However, in these studies appears uncertainty in the assignments of several bands due to lack of a good procedure for scaling the wavenumbers. In the present work we report the I.R and Raman spectra of 2,6-difluorobenzonitrile (2,6-DFBN) and observed vibrational frequencies are assigned to different normal modes of the molecule.

Code: ThP25	Time Slot/Poster Number: 052	Session: Molecular Biophysics and Photobiology II
Brillouin Light Scattering In Guanidine Hydrochloride Solutions
Anna Svanidze1; Ivan Koludarov1; Alex Fedoseev1; Sergey Lushnikov1; Seiji Kojima2
1Ioffe Physical Technical Institute RAS, St.-Petersburg, Russian Federation; 2University of Tsukuba, Tsukuba, Japan
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Summary
We have studied the temperature behavior of Brillouin light scattering in 1 M, 2 M and 6 M GdnHCl solutions prepared on the base of sodium acetate buffer (pH 4.6). In Brillouin light scattering experiments with 6 M GdnHCl solution the presence of intensive quasielastic light scattering caused by anisotropy fluctuations was revealed. Obtained data are discussed in the framework of modern approach to the low frequency dynamics of liquids.

Code: ThP25	Time Slot/Poster Number: 053	Session: Molecular Biophysics and Photobiology II
FT-IR and FT-Raman Spectra of Complex of Cu(II) with 6-Azauracil
Hitesh Kumar1; Meenakshi Sharma1; Rekha Sharma1; B K Rai1; I. Hubert Joe2; Mahesh Srivastava1; V.K. Rastogi1
1C.C.S University, Meerut, India; 2University of Kerala, Trivandrum, India
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Summary
Vibrational analysis of the Cu(II) with 6-Azauracil compound was carried out by using NIR FT-Raman and FT-IR spectroscopic techniques. The two v( N-H) modes in free ligand have been identified. Metal binding through the exocyclic oxygen is confirm from the vibrational analysis

Code: ThP25	Time Slot/Poster Number: 054	Session: Molecular Biophysics and Photobiology II
Vibrational Spectra and Nonlinear Optical properties of Acetoacetanilide
Ravikumar C.; I. Hubert Joe
University of Kerala, Trivandrum, India
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Summary
NIR FT Raman and IR spectra of the nonlinear optical crystal acetoacetanilide have been recorded and analyzed. The optimized geometry, bonding features and harmonic vibrational frequencies of acetoacetanilide have been investigated. The detailed interpretation of the vibrational spectra has been carried out with the aid of normal coordinate analysis following the scaled quantum mechanical force field methodology. The redshifting of C=O stretching wavenumbers explain the conjugation between carbonyl groups and the aromatic ring. The Kurtz and Perry powder reflection technique appeared to be very effective in studies of second order nonlinear optical properties of the molecule.

Code: ThP25	Time Slot/Poster Number: 055	Session: Molecular Biophysics and Photobiology II
FTIR, FT-Raman Spectra and AB Initio DFT Vibrational Analysis of 3-PYRIDINECARBOXYLIC acid and 2-FLLUORO-3-PYRIDINECARBOXYLIC Acid
Priyanka Singh
B.H.U, Varanasi, India
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Summary
Nicotinic acid and its derivatives i.e, 2- Fluoronicotinic acid (2-FNA) or 2-Fluoro-3-pyridinecarboxylic acid, which has good biological activities and versatile bonding modes, have been studied extensively[1]. Restricted-Hartree-Fock (RHF) and Density functional theory (DFT) calculations methods were performed using 6-311++g** and 6-311++g** basis sets have been employed to carry out the optimized geometry, atomic charges, harmonic vibrational frequencies, infrared intensities, Raman activities and depolarization ratio of the Raman bands for the NA and 2-FNA.

Code: ThP25	Time Slot/Poster Number: 056	Session: Molecular Biophysics and Photobiology II
Raman Scattering Investigation of 3(10) Helical Peptides Using Isotopic Labeling
Ahmed Lakhani1; Anjan Roy1; Marcelo Nakaema1; Matteo de Poli2; Fernando Formaggio2; Claudio Toniolo2; Timothy A. Keiderling1
1University of Illinois at Chicago, Chicago, IL; 2University of Padova, Padova, Italy
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Summary
Experimental and theoretical studies of Raman scattering spectra have been performed on 3(10)-helical synthesized peptides with two different amino-acid chain lengths: hexamers (iPrCO-Aib-L-Ala-Aib-L-Ala-L-Ala-Aib-NHiPr) and octamers (iPrCO-Aib-L-Ala-Aib-L-Ala-L-Ala-Aib-Aib-Aib-NHiPr) with and without isotopic labeling at different positions along the peptide chain. The ab initio DFT calculations predicted the relative separations of 13C=O and 12C=O features and their dependence on conformation as seen experimentally with the exception that end effects caused a change in diagonal force field not well represented in the theoretical modeling. Experimental Raman, IR and VCD spectra for the octamer confirmed the source of deviation observed for the hexamer peptides.

Code: ThP25	Time Slot/Poster Number: 057	Session: Molecular Biophysics and Photobiology II
Spectroscopic Research Of Hydrogen Bonding In Aqueous Ethanol Systems
Sergey Burikov1; Tatiana Dolenko1; Masashi Hojo2; Svetlana Patsaeva1; Victor Yuzhakov1
1Moscow State University, Physics Department, Moscow, Russian Federation; 2Kochi University, Faculty of Science, Kochi, Japan
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Summary
Raman spectroscopy of water-ethanol binary mixtures with alcohol concentration ranging from 0 to pure ethanol was performed at different temperatures. The changes in hydrogen bonding strength were estimated from contour analysis of OH stretching band.