Data from fluorescence spectroscopy, isothermal titration calorimetry, voltammetry, and vesicle electrodeformation for characterisation of lipid membranes in the presence of VV-hemorphin-5 analogues with nociceptive activity
Description
Datasets contain raw and analysed data on physicochemical parameters of 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine (POPC) membranes containing VV-hemorphin-5 (Val-Val-Tyr-Pro-Trp-Thr-Gln) and analogues, modified at position 1 and 7 by the natural amino acid isoleucine or the non-proteinogenic 2-aminoisobutyric, 2,3-diaminopropanoic or 2,4-diaminobutanoic amino acids. Peptides were chosen and their notation was kept according to [P. Todorov, P. Peneva, D. Pechlivanova, S. Georgieva, E. Dzhambazova, Synthesis, characterization and nociceptive screening of new VV-hemorphin-5 analogues, Bioorganic & Medicinal Chemistry Letters, 28 (2018) 3073-3079.]. Dataset 1 provides analysed data from Laurdan and di-8-ANEPPS fluorescence spectroscopy of large unilamellar vesicles (LUV) in the presence of valorphins. Laurdan normalised spectra and general polarisation data are reported as well as di-8-ANEPPS fluorescence intensity ratio and POPC membrane dipole potential of all valorphins studied. Dataset 2 contains analysed data on specific electrical capacitance of POPC-valorphin membranes acquired from frequency-dependent deformation of giant unilamellar vesicles (GUV) in AC field. For each membrane composition studied vesicle radii are given together with the intermediate "critical" frequencies of the AC field applied at which vesicles assume quasispherical shapes according to [P.F. Salipante, R.L. Knorr, R. Dimova, P.M. Vlahovska, Electrodeformation method for measuring the capacitance of bilayer membranes, Soft Matter, 8 (2012) 3810-3816.]. Information about the conductivity of the aqueous solutions is included. Dataset 3 describes analysed electrokinetic data of POPC-valorphin LUVs including vesicles sizes and zeta potential values. Dataset 4 reports cyclic voltammetry data of valorphin analogues in supporting electrolyte (0.1 mol L-1 phosphate buffer solution, pH 6.78 ± 0.01) recorded on a Metrohm 797 (Metrohm, Switzerland) VA trace analyser and a 797 VA stand with a Pt-disk electrode with 3 sq. mm area as a working electrode, Ag/AgCl (3 mol/L KCl) as a reference electrode and a platinum wire serving as a counter electrode. Voltamperograms were recorded in square wave voltammetric (SWV) mode at 50 Hz frequency and 2 mV potential increments corresponding to scan rate of 100 mV/s. The required aliquotes of the standard analyte solution (50-100 µL) were measured by subsequently adding them in the solution of the supporting electrolyte. Data are reported as the mean value of three independent measurements. Dataset5 contains isothermal titration calorimetry (ITC) raw data of injection heats Q of POPC LUVs' dilution in valorphin aqueous solutions. Blank data are provided from control measurements in bidistilled water. Lipid vesicles as aliquots of 2 µL were injected in 25 steps with 300 s interval and stirring speed of 250 rpm.