Department of chemistry

Ligand binding causes the EGF receptor (EGFR) to become ubiquitinated by Cbl upon association with the adaptor protein Grb2. We have investigated the role of ubiquitin and Grb2 in ligand-induced endocytosis of the EGFR. Incubation of cells with EGF on ice caused translocation of Grb2 and Cbl from the cytosol to the rim of coated pits. Grb2 with point mutations in both SH3 domains inhibited recruitment of the EGFR to clathrin-coated pits, in a Ras-independent manner. On overexpression of the Cbl-binding protein Sprouty, ubiquitination of the EGFR was inhibited, the EGFR was recruited only to the rim of coated pits, and endocytosis of the EGFR was inhibited. Conjugation-defective ubiquitin similarly inhibited recruitment of EGF-EGFR to clathrin-coated pits. Even though this does not prove that cargo must be ubiquitinated, this indicates the importance of interaction of ubiquitinated protein(s) with proteins harboring ubiquitin-interacting domains. We propose that Grb2 mediates transie...

The significance of charged residues for the target-cell binding, potency and specificity of pediocin-like bacteriocins has been studied by site-directed mutagenesis of sakacin P. Most of the charged residues are located in the N-terminal half, which is thought to mediate the initial binding of these bacteriocins to target cells through electrostatic interaction. All the mutated peptides in which the net positive charge was reduced by one (by replacing a charged residue with threonine) exhibited reduced binding to target cells and a 2-15-fold reduction in potency. The least deleterious of these mutations was the removal of the positive charge in position 8 (H8T). This mutation was, in fact, less deleterious than the conservative His to Lys mutation, indicating that the positive charge in position 8 per se is not of major importance. Somewhat more deleterious was the removal of positive charges at the N- and C-terminal ends (K1T, K43T). Most deleterious was the elimination of the pos...

Polychlorinated dibenzo dioxins (PCDDs) are group of chlorinated organic compounds widely known as dioxins and their toxicity is depending on the position and the number of chlorine atoms. 17 out of 210 which are known today, are toxic. 2,3,7,8-TCDD (tetrachlorodibenzo-para-dioxin) is the best known and most toxic dioxin. In daily life, human exposure to toxins can be enviromental, occupational or accidental. Most dioxins are produced and released by human activities such as industrial processes and incomplete combustion. General population is exposed to background or enviromental dioxins through food or other products containing dioxins. 2,3,7,8-TCDD was evaluated as carcinogenic to humans by IARC in 1998. This was based on most recent epidemiologic data on exposed human population (accidental exposure) and there is a strong evidence of increased risk for all cancers combined. Experimental data in laboratory animals show sufficient evidence of carcinogenity of 2,3,7,8-TCDD who was ...

The present study aimed to investigate the influence of different rootstocks (Gisela 6, Pi-Ku 1, and SL 64) on various parameters, including total phenol content, total anthocyanin content, individual phenol content, and antioxidant activity in the fruits of two sweet cherry cultivars, namely Early Lory and Prime Giant. The determination of total phenolic content was carried out using the Folin-Ciocalteu reagent and spectrophotometric method, resulting in a range of 34.77±1.76 to 88.58±8.83 mg GAE/100 g FW, depending on the specific combination of cultivar and rootstock. The concentration of total anthocyanins, determined through the pH-differential method, varied from 1.08±0.07 to 18.62±0.66 mg CGE/100 g FW. Among the different combinations, the highest levels of total phenolic content and total anthocyanin concentration were found in Early Lory cultivar grafted onto Pi-Ku 1 rootstock. Using HPLC analysis, neochlorogenic acid, catechin, chlorogenic acid, p-coumaric acid and quercetin-3-O-glucoside were detected as individual phenols, exhibiting significant variation among sweet cherry fruits grafted on different rootstocks. The lowest content of the investigated individual polyphenols was observed in Early Lory grafted onto Pi-Ku 1 rootstock. Furthermore, the ferric reducing antioxidant power assay indicated higher antioxidant activity in Early Lory cultivar compared to Prime Giant. A statistically significant correlation was observed between total phenolic content and antioxidant activity (0.978 p<0.01), as well as between anthocyanins and antioxidant activity (0.956 p<0.01).

Sweet cherry (Prunus avium L.) presents one of the most popular fruits worldwide based on its high content of many phytonutrients and bioactive compounds which may significantly contribute to a health-promoting activity (Gonçalves et al. 2018). Bioactive compounds in sweet cherries are mostly polyphenols, including phenolic acids and flavonoids, which are associated with their antioxidant activity (Gonçalves et al. 2004; Usenik et al. 2008; González-Gómez et al. 2010; Usenik et al. 2010; Pacifico et al. 2014). It is generally known that phenolic compounds have a protective effect against oxidative stress (Szajdek, Borowska 2008), and numerous studies have identified various beneficial health effects associated with their intake (Antognoni et al. 2020; Domínguez-Perles et al. 2020). Several studies have shown a direct relation between the levels of phenolic compounds and antioxidant activity in cherry extracts (Tomás-Barberán et al. 2013). The production of sweet cherry in the world, and in Bosnia and Herzegovina, has been constantly increasing for the last 20 years. In 2023, sweet cherry was grown on 5.479 ha and 9.715 t were produced

Napad sarinom na podzemnu željezničku stanicu u Tokiju 1995.godine, praćeno napadom sarina na Matsumoto, došlo je kao „poziv buđenja“ za anti nuklearni,biloški i hemijski terorizam u svijetu.
U napadu nervnim gasom sarinom na vozove koji su ulazili u stanice tokijskog metroa koje naročito često koriste poslanici parlamenta, činovnici obližnjih ministarstava i sudova, 20. marta 1995. godine poginulo je 13, a povrijeđeno oko 6.300 ljudi. Napad na prijestonički metro izveden je u trenutku kada su članovi sekte bili pod prismotrom policije i prijetili su im zabrana i hapšenja zbog ranijih zločina. Prije Tokija, sarin su iskoristili u gradu Matsumotu 1994. godine, kada je poginulo osam i povrijeđeno 200 ljudi.