The aim of this study is to evaluate the role of amino acid changes in the natural missense mutations of the hCYP51A1 protein. We searched SNP databases for existing polymorphisms of CYP51A1 and evaluated their effect on protein function. We found rare variants causing detrimental missense mutations of CYP51A1.
B.03 Paper at an international scientific conference
COBISS.SI-ID: 6312730Organic cathode materials can be used in various battery systems like lithium, sodium, magnesium batteries and can be prepared from low-cost and sustainable resources, which makes them one of the promising materials for future batteries. One of the pressing issues of contemporary research on the cathode materials was the lack of characterization techniques that would allow real-time monitoring of changes inside cathodes during electrochemical cycling. With the financing from the Honda R&D Europe and Slovenian Research agency and joint effort from two departments we developed a new method of probing changes inside the cathodes through IR spectroscopy. Method was developed for explanation of poly (anthraquinonyl) sulfide polymer in Li and Mg batteries. In both systems we observed reduction of carbonyl bond during discharge of the battery. The results of IR measurements were confirmed through calculation of theoretical spectra and synthesis of model compounds. New method presents a powerful tool for research of new organic cathode materials and study of degradation processes inside cathodes. Confirmation of the discharge mechanism in Mg battery system opens new possibilities in research of Mg‒organic batteries, where we are successfully cooperating with Honda R&D Europe in the last five years.
B.03 Paper at an international scientific conference
COBISS.SI-ID: 6189082Observation of structural changes during the hydration process of Concanavalin A, Chymotrypsinogen A, Pepsin and Stefin B protein films reveals that hydration stimulates the formation of β-structures. Despite the fact that the observed changes are not big, we are able to detect them by various methods of vibrational spectroscopy. We introduced a method which can determine thickness of protein films, based on composition of amino acids in individual protein and calibration curve prepared in the case of BSA protein films with different thickness. Number of water molecules bounded to one polypeptide chain at different rates of relative humidity (10 % - 90 %) was determined. Knowing that we are able to monitor small structural changes, which occur during the hydration processes, we applied vibrational spectroscopy to follow up conformational changes during the aggregation processes of Concanavalin A and Stefin B. In basic environment Concanavalin A forms amyloid aggregates while in acidic environment it forms amorphous aggregates. We followed up structural changes at both thermodynamically driven processes and from obtained data we defined spectral markers, which differ between both types of morphologically different aggregates. In addition to thermodynamically driven processes we followed up kinetically driven process of Concanavalin A aggregation at pH 9. All conformational changes were quantified by spectral band decomposition method. Thermodynamically driven aggregation of Stefin B was monitored at pH 3, 5, 7,5 and 9. At all pH values Stefin B forms amyloid aggregates. Transition temperature is increasing with pH values. Based on our results we proposed a new model which could describe the process of Stefin B amyloid fibril formation. This model does not foresee complete unfolding of polypeptide chain, but only partial restructuring of α-helix and β-sheets in a way to allow the formation of cross β-sheets, a typical structural element of amyloid fibrils.
D.09 Tutoring for postgraduate students
COBISS.SI-ID: 289386752In drug development, it is important to have a suitable crystalline form of the active substance. Substances that are stable only within a certain pH range are a challenge for the formulation developement. Omeprazole molecule belongs to the group of prazoles; drugs which are proton pump inhibitors in the human body, but their main characteristic is a strong and long-lasting reduction of gastric acid formation. For the prazoles, it is known to be sensitive to degradation in an acid environment. The formulation is then stabilized with alkaline additives or is used in the form of basic salts. Preparation and characterization of basic salts is needed in the case of use in the formulation and to monitor any possible salinization of free molecule. For purposes of this study, the salts of omeprazole from the group of alkali metal (Li, Na, K) and alkaline earth metals (Mg, Ca) were synthesized. Also the physicochemical properties of five salts were probed, using Fourier-transform infrared and Raman microscopy, hot stage, dynamic vapour sorption, nuclear magnetic resonance, thermogravimetry, differential scanning calorimetry and theoretical calculation of vibrational frequencies. It was found, that vibrational spectroscopy serves as appropriate spectroscopic tool which in accurate, quick and non-destructive way determines the physicochemical characteristics of omeprazole and its salts.
D.09 Tutoring for postgraduate students
COBISS.SI-ID: 6315034Molecular solutes are known to have a strong effect on structural and dynamical properties of the surrounding water. Depending on perturbations by a solute the water hydrogen-bond network can either locally relax to configurations of optimal intermolecular angles or decouple from the network. In our study we have applied ab-initio molecular dynamics simulations and identified the relationship between the appearance of the strengthened water hydrogen bonds near hydrophobic solutes and structural and dynamical changes evaluated by the proper order parameters.
B.03 Paper at an international scientific conference
COBISS.SI-ID: 6343450