3rd International Conference on Chemo and BioInformatics, Kragujevac, September 25-26, 2025. (pp. 48-52)
АУТОР(И) / AUTHOR(S): Petra Maleš, Barbara Pem, Danijela Bakarić
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DOI: 10.46793/ICCBIKG25.048M
САЖЕТАК / ABSTRACT:
As a continuation of our research on model myelin membranes (MMM), in which we revealed that MMM that mimic normal (healthy) myelin are more fluid at 30 °C than those that mimic modified (diseased) myelin, we aimed to unveil the contribution of cholesterol in MMM thermotropic properties. Accordingly, we prepared MMM as lipid mixtures in the presence and absence of myelin basic protein (MBP), but excluding cholesterol (named MMM’). Using differential scanning calorimetry (DSC) and temperature-dependent UV-Vis spectroscopy, we determined the main phase transition temperature (Tm) of MMM’, i.e., the temperature of the gel- to-fluid phase transition of lipids in MMM’ systems. Besides the discrepancies obtained by these two techniques, we identified a difference of about 5 °C between normal and modified MMM’, independently of MBP. As evidenced by the maintenance and weakening of van der Waals forces at 30 °C and 60 °C, respectively, the fluidity of normal and modified MMM’ is comparable at a corresponding temperature. The modified MMM’ reflected different polar headgroup hydration than normal MMM’ at 30 °C, which is very likely associated with the stabilization of the gel phase in modified MMM’.
КЉУЧНЕ РЕЧИ / KEYWORDS:
model myelin membranes, cholesterol, myelin basic protein, thermotropic properties
ПРОЈЕКАТ / ACKNOWLEDGEMENT:
This research is funded by the Croatian Science Foundation, Project HRZZ UIP-2020-02- 7669. P. M. and D. B. gratefully acknowledge members of the Laboratory for biocolloids and surface chemistry (Division for Physical Chemistry, Ruđer Bošković Institute) for access to the Zetasizer Nano ZS (Malvern).
ЛИТЕРАТУРА / REFERENCES:
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- P. Maleš, B. Pem, D Petrov. A. Mangiarotti, R. Dimova, D. Bakarić, submitted.
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