IR and turbidity studies of vitamin E-cholesterol-phospholipid membrane interactions

Severcan, Feride
Kazanci, Nadide
Baykal, Ülkü
Süzer, Şefik
Binary and tertiary mixture of α-tocophenol, cholesterol and dimyristoylphosphatidylcholine in the form of multilamellar liposomes were investigated by Fourier Transform Infrared and visible spectroscopy. Results of the FTIR and turbidity experiments indicate that α T decreases or diminishes the effect of cholesterol on the frequency and the bandwidth of the C-H stretching, CH2 scissoring and C=O stretching bands in FTIR spectra and the turbidity measurements (recorded as absorbance values at 440 nm) in phospholipid model membranes.
Bioscience Reports


Using artificially generated spectral data to improve protein secondary structure prediction from Fourier transform infrared spectra of proteins
Severcan, M; Haris, PI; Severcan, Feride (Elsevier BV, 2004-09-15)
Secondary structures of proteins have been predicted using neural networks from their Fourier transform infrared spectra. To improve the generalization ability of the neural networks, the training data set has been artificially increased by linear interpolation. The leave-one-out approach has been used to demonstrate the applicability of the method. Bayesian regularization has been used to train the neural networks and the predictions have been further improved by the maximum-likelihood estimation method. T...
Effect of progesterone on DPPC membrane: Evidence for lateral phase separation and inverse action in lipid dynamics
Korkmaz, F; Severcan, Feride (Elsevier BV, 2005-08-15)
Interactions of progesterone with zwitterionic dipalmitoyl phosphatidylcholine (DPPC) triultilamellar liposomes were investigated as a function of temperature and progesterone concentration by using three non-invasive techniques namely Fourier transform infrared spectroscopy, turbidity at 440 nm, and differential scanning calorimetry. The results reveal that progesterone changes the physical properties of DPPC bilayers by decreasing the main phase-transition temperature, abolishing the pre-transition, broad...
Vitamin E Decreases the Order of the Phospholipid Model Membranes in the Gel Phase: An FTIR Study
Severcan, Feride (Portland Press Ltd., 1997-4-1)
The effect of α-tocopherol on the frequency of the CH2 stretching bands of infrared spectra of dipalmitoylphosphotidylcholine multibilayers has been investigated, both in H2O and 2H2O buffer, to determine the reason for the discrepancy in the literature between the results of different spectroscopic techniques relating to the effect of α-tocopherol on membrane order in the gel phase. In contrast to previous FTIR studies, the present FTIR results indicate that αT increases the frequencies of the CH2 stretchi...
Structural properties of an engineered outer membrane protein G mutant, OmpG-16SL, investigated with infrared spectroscopy
Yilmaz, Irem; Yildiz, Ozkan; KORKMAZ ÖZKAN, FİLİZ (Informa UK Limited, 2019-05-31)
The structural and functional differences between wild type (WT) outer membrane protein G and its two mutants are investigated with Fourier transform infrared spectroscopy. Both mutants have a long extension to the primary sequence to increase the number of beta-strands from 14 (wild type) to 16 in an attempt to enlarge the pore diameter. The comparison among proteins is made in terms of pH-dependent conformational changes and thermal stability. Results show that all proteins respond to pH change but at dif...
Tip enhanced Raman scattering with adiabatic plasmon focusing tips.
Bek, Alpan; DAS, G; Di, Fabrizio; LAZZARINO, M (Elsevier BV, 2011-06-01)
Tip-Enhanced Raman spectroscopy (TERS) is a promising microscopy technique which combines, in principle, outstanding spatial resolution with a detailed chemical analysis of the sample. However, as yet, it is not routinely used although an increasing number of research groups are becoming more actively involved in the field. Among the several reasons which can explain the relatively low usage of TERS, the lack of reproducibility of tips as field enhancers is probably the most critical. Here we propose and de...
Citation Formats
F. Severcan, N. Kazanci, Ü. Baykal, and Ş. Süzer, “IR and turbidity studies of vitamin E-cholesterol-phospholipid membrane interactions,” Bioscience Reports, pp. 221–229, 1995, Accessed: 00, 2020. [Online]. Available: