20.500.12556/RUL-171840 Vpliv bakrovih ionov na vezavo N-acetil-D-laktozamina na lizocim The influence of copper ions on the binding of N-acetyl-D-lactosamine to lysozyme Porušena homeostaza kovinskih ionov lahko vodi do oksidativnega stresa, ki spodbuja nepravilno zvijanje in agregacijo proteinov, kar je povezano z različnimi patološkimi stanji. V sklopu diplomskega dela smo raziskali vpliv bakrovih (Cu$^{2+}$) ionov na vezavo N-acetil-D-laktozamina (LacNAc) na lizocim iz kokošjega jajčnega beljaka (HEWL). Vezavo LacNAc na HEWL in vpliv Cu$^{2+}$ ionov smo spremljali z UV-Vis in fluorescentno spektroskopijo. Vpliv Cu$^{2+}$ ionov na sekundarno strukturo in termostabilnost HEWL smo spremljali z CD-spektroskopijo in diferenčno dinamično kalorimetrijo (DSC). Mesto vezave LacNAc na HEWL smo napovedali z molekulskim sidranjem. Z analizo fluorescentnih emisijskih spektrov smo potrdili vezavo LacNAc na HEWL in da Cu$^{2+}$ ioni spremenijo interakcijo med LacNAc in HEWL. Z molekulskim sidranjem smo napovedali, da se LacNAc veže v vrzel aktivnega mesta. Iz elektrostatskega potenciala na HEWL je razvidno, da je v vrzeli aktivnega mesta področje z negativnim potencialom, ki lahko predstavlja potencialno vezavno mesto za Cu$^{2+}$ ione. Cu$^{2+}$ ioni pod preiskovanimi pogoji niso povzročili opaznih sprememb v sekundarni strukturi in niso povzročili signifikantne destabilizacije HEWL. Iz teh rezultatov smo sklepali, da Cu$^{2+}$ ioni vplivajo na vezavo LacNAc na HEWL tako, da tekmujejo za isto vezavno mesto. Disruption of metal ion homeostasis can lead to oxidative stress, which promotes protein misfolding and aggregation linked to several pathological conditions. The aim of our research was to investigate the influence of copper (Cu$^{2+}$) ions on the binding of N-acetyl-D-lactosamine (LacNAc) to hen egg white lysozyme (HEWL). UV-Vis and fluorescence spectroscopy were used to monitor the interaction between LacNAc, Cu$^{2+}$ ions and HEWL. The effect of copper ions on the secondary structure and the thermostability of HEWL were assessed using circular dichroism (CD) spectroscopy and differential scanning calorimetry (DSC), respectively. Molecular docking was used to predict the location of the binding site of LacNAc on HEWL. Fluorescence emission spectra analysis confirmed the binding of LacNAc to HEWL and indicated that Cu$^{2+}$ ions modulate the interaction between LacNAc and HEWL. Molecular docking predicted that LacNAc binds in the active site cleft of HEWL. The electrostatic potential map for HEWL showed an area with negative potential within the active site cleft, which could be a possible binding site for Cu$^{2+}$ ions. Cu$^{2+}$ ions do not cause substantial changes in the protein’s secondary structure under the conditions studied and they do not significantly destabilize HEWL. From these results, we suggest that Cu$^{2+}$ ions modulate the binding of LacNAc by competing for a common binding site. vezava lizocim N-acetil-D-laktozamin bakrovi ioni binding lysozyme N-acetyl-D-lactosamine copper ions true false false Slovenski jezik Angleški jezik Diplomsko delo/naloga 2025-09-03 10:40:01 2025-09-03 10:40:08 2025-10-09 11:04:49 0000-00-00 00:00:00 2025 0 0 0000-00-00 NiDoloceno NiDoloceno NiDoloceno 0000-00-00 0000-00-00 0000-00-00 25604 252460291 Bregar_Jana_-_Vpliv_bakrovih_ionov_na_vezavo_N-acetil-D-laktozamina_na_lizocim.pdf Bregar_Jana_-_Vpliv_bakrovih_ionov_na_vezavo_N-acetil-D-laktozamina_na_lizocim.pdf 1 867B26E269D90712BC61BCA4778162A5 620dc796e94852875c3b748b8faccc101fc1c246eec2fca4fb07c80061ac5539 74bd3222-88a1-11f0-9328-0050569b8976 https://repozitorij.uni-lj.si/Dokument.php?lang=slv&id=215348 Fakulteta za kemijo in kemijsko tehnologijo 0 0 0