Cloning of an engenieered histone cluster in Drosophila melanogaster

Unrepaired DNA damages could lead to cancer formation. To allow repair of these damages, the repair proteins must assess the damage site, so the condensed DNA needs to be looser. Our group is interested in to understand chromatin changes during DNA repair processes by using novel experimental system. In eukaryotic cells the nucleus contains highly condensed DNA. The base of the chromatin structure is the evolutionarily conserved histone protein family. The histone proteins necessary for nucleosome assembly by forming a heterooctamer with two copies of H2A, H2B, H3 and H4. Finally the linker histone H1 requires for the proper chromatin condensation. All of the histone proteins can be post-translationally modified. These PTMs are the main rulers of epigenetic regulation. Processes using DNA as a template (transcription, replication and DNA repair) are greatly affected by the chromatin structure. Unimproved breaks lead genome instability or translocations which easily results tumor formation. Our aim is to understand how does the chromatin structure change around the break during the DNA repair and what is the link between unique histone PTMs and the mechanisms of the repair. We plan to set up an experimental system by which we will be able to study how do unique histone modifications affect the DSB repair. The advantage of this new experimental system is the clone of the histone cluster which contains all of the canonic (H2A, H2B, H3, H4) and linker (H1) histone genes in Drosophila melanogaster

A kiskorúak online aktivitásának kriminológiai értelmezése, különös tekintettel az állam és a szülők szerepére

The linking media studies and criminology, the author provides an overview for avenues of preventing youth online deviance in Hungary.A médiatanulmányok és a kriminológia összekapcsolásával a szerző áttekintést nyújt az ifjúsági online deviancia megelőzésének lehetőségeiről

Fumonizineket-termelő Fusarium verticillioides genotípusok azonosítása, elterjedésük felmérése a hazai kalászos gabona- és kukorica-termőhelyeken = Determination of fumonisins-producing genotypes of Fusarium verticillioides associated with small-grain cereals and maize in Hungary

A fumonizinek 1988 óta ismert mikotoxinok, amelyeket négy csoportba (A, B, C, P) sorolnak. Toxikológiai szempontból a B-csoportba tartozó fumonizinek (FB1, FB2, FB3, FB4) a legfontosabbak. A Fusarium verticillioides amely a kukorica kórokozója, a legfontosabb fumonizin-termelő penészgomba. A F. verticillioides tiszta, rizstenyészeteiben képzödő fumonizinek 70-80%-a FB1. Az általunk használt érzékeny, egyben szelektív módszer az RP-HPCL/ESI-IT-MS esetében csökken a műtermék képződés lehetősége, valamint a gombatenyészetekből készített kivonatok további tisztitása nélkül használhatok eddig ismeretlenfumonizin-analógok kimutatására és azonosítására. Optimalizáltuk az RP-HPLC elválasztás körülményeit, valamint a rizstenyészetekből történő fumonizin kivonás paramétereit is. Hatvan F. verticillioides, egyspórás genotípusainak rizstenyészet kivonatának vizsgálata során egyrészt kimutattunk az A-, B-, C-, P-csoportba tartozó fumonizineket, másrészt új eddig leíratlan fumonizineket is találtunk. Jelenleg 124 fumonizin-típusú anyagcseretermék feldolgozása folyik. A különböző szubsztrátumokról származó hatvan hazai származású F. verticillioides genotípus B-csoportba tratozó fumonizinjeinek minőségi és mennyiségi jellemzőit vizsgáltuk. Eredményeink alapján feltételezzük fumonizin kemotípusok létezését, amely erdmények közlése folyamatban van (Szécsi et al. 2008: Occurring of fumonisin chemotypes in Hungarian Fusarium verticillioides population. Kézírat). | Fumonisins were produced in a rice culture infected with Fusarium verticillioides. To decrease the possibility of the formation of artifacts, the fumonisins were analyzed by reversed-phase high-performance liquid chromatography with electrospray ionization ion trap tandem mass spectrometry (RP-HPLC/ESI-IT-MS) immediately after the extraction of the culture material without any sample clean-up. In addition to already known fumonisins (FA, FB, FC, FP), numerous new fumonisin mycotoxins and fumonisin-like compounds (124) were detected. On the basis of the IT-MS data, detailed fragmentation pathways including new mechanisms were proposed for the different series of fumonisins. Most field isolates of F. verticillioides produce the full complement of FB1, FB2, FB3, and FB4. Fumonisin-nonproducing isolates were not in investigated population. In this study, we examined diversity of fumonisin chemotypes of Hungarian field isolates of F. verticillioides

Biological Purification of Chemically Pre-Treated Dairy Wastewater Before Discharge into a Municipal Sewage Systems

Dairy production is one of the most inefficient processes with respect to water usage in the food industry. It was estimated that the production of a litre of milk creates three to four litres of wastewater. Dairy wastewater contains a high amount of dissolved and suspended solids. Moreover, it contains high concentrations of fat, protein, and carbohydrate. Consequently, the dairy wastewater content of organic compounds is high and so is its chemical oxygen demand. The majority of organic compounds are biodegradable with a high biological and chemical oxygen demand ratio. In this work, we examined the biological purification of physico- chemically pretreated wastewater from a Hungarian milk-processing factory before it was discharged into the public sewage system. The chemical oxygen demand of the pre-treated wastewater ranged from 500 to 2500 mg dm-3. We found that it was possible to achieve efficient organic material removal from nutrient-poor wastewater without nutrient dosage contrary to the literature. The activated sludge system manifested efficient organic material removal that required a smaller biological volume. Experiments with biofilms have shown that a thicker biofilm needs more dissolved oxygen, which dictates oxygen input levels to be sufficient for creating an aerobic environment