TY - JOUR AU - Howan, Dian Herlinda Octorina AU - Jenei, Sándor AU - Szolomájer, János AU - Endre, Gabriella AU - Kondorosi, Éva AU - Tóth, Gábor TI - Enhanced Antibacterial Activity of Substituted Derivatives of NCR169C Peptide JF - INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES J2 - INT J MOL SCI VL - 24 PY - 2023 IS - 3 PG - 13 SN - 1661-6596 DO - 10.3390/ijms24032694 UR - https://m2.mtmt.hu/api/publication/33611580 ID - 33611580 N1 - Export Date: 18 April 2023 AB - Medicago truncatula in symbiosis with its rhizobial bacterium partner produces more than 700 nodule-specific cysteine-rich (NCR) peptides with diverse physicochemical properties. Most of the cationic NCR peptides have antimicrobial activity and the potential to tackle antimicrobial resistance with their novel modes of action. This work focuses on the antibacterial activity of the NCR169 peptide derivatives as we previously demonstrated that the C-terminal sequence of NCR169 (NCR169C17–38) has antifungal activity, affecting the viability, morphology, and biofilm formation of various Candida species. Here, we show that NCR169C17–38 and its various substituted derivatives are also able to kill ESKAPE pathogens such as Enterococcus faecalis, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, and Escherichia coli. The replacement of the two cysteines with serines enhanced the antimicrobial activity against most of the tested bacteria, indicating that the formation of a disulfide bridge is not required. As tryptophan can play role in the interaction with bacterial membranes and thus in antibacterial activity, we replaced the tryptophans in the NCR169C17–38C12,17/S sequence with various modified tryptophans, namely 5-methyl tryptophan, 5-fluoro tryptophan, 6-fluoro tryptophan, 7-aza tryptophan, and 5-methoxy tryptophan, in the synthesis of NCR169C17–38C12,17/S analogs. The results demonstrate that the presence of modified fluorotryptophans can significantly enhance the antimicrobial activity without notable hemolytic effect, and this finding could be beneficial for the further development of new AMPs from the members of the NCR peptide family. LA - English DB - MTMT ER - TY - JOUR AU - Sebák, Fanni AU - Szolomájer, János AU - Papp, Nándor AU - Tóth, Gábor AU - Bodor, Andrea TI - Proline cis/trans Isomerization in Intrinsically Disordered Proteins and Peptides JF - FRONTIERS IN BIOSCIENCE-LANDMARK J2 - FRONT BIOSCI-LANDMARK VL - 28 PY - 2023 IS - 6 PG - 8 SN - 2768-6701 DO - 10.31083/j.fbl2806127 UR - https://m2.mtmt.hu/api/publication/34043118 ID - 34043118 N1 - Analytical and BioNMR Laboratory, Institute of Chemistry, Eötvös Loránd University, Budapest, 1117, Hungary Department of Medical Chemistry, University of Szeged, Szeged, 6720, Hungary Hevesy György PhD School of Chemistry, Eötvös Loránd University, Budapest, 1117, Hungary Export Date: 28 July 2023 Correspondence Address: Bodor, A.; Analytical and BioNMR Laboratory, Hungary; email: andrea.bodor@ttk.elte.hu Chemicals/CAS: proline, 147-85-3, 7005-20-1; Intrinsically Disordered Proteins; Peptides; Proline LA - English DB - MTMT ER - TY - JOUR AU - Angeli, Cserne AU - Nagy, Tamás Milán AU - Horváth, Levente AU - Varga, Mónika AU - Szekeres, András AU - Tóth, Gábor AU - Janáky, Tamás AU - Szolomájer, János AU - Kovács, Melinda AU - E Kövér, Katalin AU - Bartók, Tibor TI - Preparation of 3- O -, 5- O - and N -palmitoyl derivatives of fumonisin B 1 toxin and their characterisation with NMR and LC-HRMS methods JF - FOOD ADDITIVES AND CONTAMINANTS PART A - CHEMISTRY ANALYSIS CONTROL EXPOSURE AND RISK ASSESSMENT J2 - FOOD ADDIT CONTAM A VL - 39 PY - 2022 IS - 10 SP - 1759 EP - 1771 PG - 13 SN - 1944-0049 DO - 10.1080/19440049.2022.2116112 UR - https://m2.mtmt.hu/api/publication/33085154 ID - 33085154 AB - We have previously published six esterified O-acyl (EFB1) and three N-acyl fumonisin B-1 derivatives extracted from rice cultures inoculated with Fusarium verticillioides, amongst these the identification of N-palmitoyl-FB1 has been clearly established in a spiking experiment. At that time, it was assumed that as in the case of O-acyl-FB1 derivatives, linoleic-, oleic- or palmitic acid esterify through the OH group on the 3C or 5C atom of the carbon chain of the fumonisins. In our most recent experiments, we have synthetically acylated the FB1 toxin and subsequently purified 3-O-palmitoyl- and 5-O-palmitoyl-FB1 toxins in addition to the N-palmitoyl-FB1 toxin. They were identified and characterised using H-1 and C-13 NMR as well as LC-HRMS. Our aim was the identification of the previously detected O-acyl-FB1 derivatives over the course of a spiking experiment, which were obtained through the solid-phase fermentation of Fusarium verticillioides. By spiking the three synthesized and identified components one-by-one into the fungal culture extract and analysing these cultures using LC-MS, it was clearly demonstrated that the F. verticillioides strain produced both the 5-O-palmitoyl-FB1 and N-palmitoyl-FB1 toxins, but did not produce 3-O-palmitoyl-FB1. Thus, it is highly probable that the components thought to be 3-O-acyl-(linoleoyl-, oleoyl-, palmitoyl-) FB1 derivatives in our previous communication are presumably 10-O-acyl-FB1 derivatives. Since these acylated FB1 derivatives can occur naturally in e.g. maize, the use of these synthesized components as reference materials is of great importance in order to obtain accurate qualitative and quantitative data on the occurrence of acylated fumonisins in different matrices including maize based feed samples. The production of these substances has also made it possible to test their toxicity in cell culture and small animal experiments. LA - English DB - MTMT ER - TY - JOUR AU - Szolomájer, János AU - Stráner, Pál AU - Kele, Zoltán AU - Tóth, Gábor AU - Perczel, András TI - Synthesis of the extracellular domain of GLP-1R by chemical and biotechnological approaches JF - RSC ADVANCES J2 - RSC ADV VL - 12 PY - 2022 IS - 37 SP - 24278 EP - 24287 PG - 10 SN - 2046-2069 DO - 10.1039/D2RA02784D UR - https://m2.mtmt.hu/api/publication/33071352 ID - 33071352 N1 - Department of Medical Chemistry, Albert Szent-Györgyi Medical School, University of Szeged, Szeged, H-6720, Hungary MTA-ELTE Protein Model. Res. Group and Laboratory of Structural Chemistry and Biology, Pázmány P. stny. 1/A, Budapest, 1117, Hungary Laboratory of Structural Chemistry and Biology, Institute of Chemistry, ELTE Eötvös Loránd University, Pázmány P. stny. 1/A, Budapest, 1117, Hungary MTA-SZTE Biomimetic Research Group, University of Szeged, Szeged, H-6720, Hungary Export Date: 5 April 2023 CODEN: RSCAC Correspondence Address: Tóth, G.K.; Department of Medical Chemistry, Hungary; email: toth.gabor@med.u-szeged.hu Correspondence Address: Perczel, A.; MTA-ELTE Protein Model. Res. Group and Laboratory of Structural Chemistry and Biology, Pázmány P. stny. 1/A, Hungary; email: perczel@chem.elte.hu AB - The extracellular domain of the glucagon-like peptide-1 receptor, GLP-1R, is responsible for the binding of GLP-1, and a handful of additional agonists (such as exenatide, lixisenatide, and liraglutide) used daily for treating type II diabetes mellitus. Lead discovery and optimization, however, require binding studies, which, in turn, necessitate the total synthesis of GLP-1R, comprising 108 residues. A protein domain of 10–15 kDa size could be obtained either by expression in E. coli or by ligating solid-phase peptide synthesis (SPPS)-made fragments. However, direct overexpression fails to give a properly folded protein, as GLP-1R forms an inclusion body, which fails to refold due to improper disulfide pairing. Several bacterial strains, constructs, and fusion partners were probed and it was found that only co-expression with MBP gave a 3D-fold allowing the native disulfide bond pattern formation. Some fusion partners can act as covalently linked or in situ chaperones for guiding the refolding of GLP-1R toward success. Therefore, the bottleneck to preparing GPCR extracellular domains is the correct pairing of the Cys residues. As a proof-of-concept model, nGLP1-R was made by SPPS to form the purified full-length polypeptide chain, subjected to self-guided or spontaneous Cys pairing. However, the formation of correct SS-pairs was lagging behind any protocol in use support, and the bottleneck of large-scale protein production relies on the risky step of proper refolding, which is sometimes possible only if a suitable fusion partner effectively helps and catalysis of the correct disulfide formation. LA - English DB - MTMT ER - TY - JOUR AU - Sebák, Fanni AU - Horváth, Lilla AU - Kovács, Dániel AU - Szolomájer, János AU - Tóth, Gábor AU - Babiczky, Ákos AU - Bősze, Szilvia AU - Bodor, Andrea TI - Novel Lysine-Rich Delivery Peptides of Plant Origin ERD and Human S100: The Effect of Carboxyfluorescein Conjugation, Influence of Aromatic and Proline Residues, Cellular Internalization, and Penetration Ability JF - ACS OMEGA J2 - ACS OMEGA VL - 6 PY - 2021 IS - 50 SP - 34470 EP - 34484 PG - 15 SN - 2470-1343 DO - 10.1021/acsomega.1c04637 UR - https://m2.mtmt.hu/api/publication/32491001 ID - 32491001 N1 - Export Date: 30 May 2022 Correspondence Address: Bodor, A.; Institute of Chemistry, Pázmány Péter sétány 1/a, Hungary; email: andrea.bodor@ttk.elte.hu AB - The need for novel drug delivery peptides is an important issue of the modern pharmaceutical research. Here, we test K-rich peptides from plant dehydrin ERD14 (ERD-A, ERD-B, and ERD-C) and the C-terminal CPP-resembling region of S100A4 (S100) using the 5(6)-carboxyfluorescein (Cf) tag at the N-terminus. Via a combined pH-dependent NMR and fluorescence study, we analyze the effect of the Cf conjugation/modification on the structural behavior, separately investigating the (5)-Cf and (6)-Cf forms. Flow cytometry results show that all peptides internalize; however, there is a slight difference between the cellular internalization of (5)- and (6)-Cf-peptides. We indicate the possible importance of residues with an aromatic sidechain and proline. We prove that ERD-A localizes mostly in the cytosol, ERD-B and S100 have partial colocalization with lysosomal staining, and ERD-C mainly localizes within vesicle-like compartments, while the uptake mechanism mainly occurs through energy-dependent paths. LA - English DB - MTMT ER - TY - JOUR AU - Szerencsés, Bettina AU - Gácser, Attila AU - Endre, Gabriella AU - Racskóné Domonkos, Ildikó AU - Tiricz, Hilda AU - Vágvölgyi, Csaba AU - Szolomájer, János AU - Howan, Dian Herlinda Octorina AU - Tóth, Gábor AU - Pfeiffer, Ilona AU - Kondorosi, Éva TI - Symbiotic NCR Peptide Fragments Affect the Viability, Morphology and Biofilm Formation of Candida Species JF - INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES J2 - INT J MOL SCI VL - 22 PY - 2021 IS - 7 PG - 20 SN - 1661-6596 DO - 10.3390/ijms22073666 UR - https://m2.mtmt.hu/api/publication/31953278 ID - 31953278 N1 - Department of Microbiology, Faculty of Science and Informatics, University of Szeged, Szeged, H-6726, Hungary Biological Research Centre, Institute of Plant Biology, Szeged, H-6726, Hungary Department of Medical Chemistry, University of Szeged, Szeged, H-6720, Hungary MTA-SZTE Biomimetic Systems Research Group, University of Szeged, Szeged, H-6720, Hungary Export Date: 26 April 2021 Correspondence Address: Kondorosi, E.; Biological Research Centre, Hungary; email: eva.kondorosi@gmail.com Department of Microbiology, Faculty of Science and Informatics, University of Szeged, Szeged, H-6726, Hungary Biological Research Centre, Institute of Plant Biology, Szeged, H-6726, Hungary Department of Medical Chemistry, University of Szeged, Szeged, H-6720, Hungary MTA-SZTE Biomimetic Systems Research Group, University of Szeged, Szeged, H-6720, Hungary Export Date: 1 May 2021 Correspondence Address: Kondorosi, E.; Biological Research Centre, Hungary; email: eva.kondorosi@gmail.com LA - English DB - MTMT ER - TY - CHAP AU - Tóth, Gábor AU - Bogár, Ferenc AU - Bozsó, Zsolt AU - Szolomájer, János AU - Kele, Zoltán AU - Csóti, Ágota AU - Szántó, Gábor Tibor AU - Panyi, György ED - Rakonczay, Zoltán ED - Kiss, Lóránd TI - Design and synthesis of selective ion channel blocker peptide toxin analogues T2 - Proceedings of the EFOP-3.6.2-16-2017-00006 (LIVE LONGER) project PB - University of Szeged CY - Szeged SN - 9789633067642 PY - 2020 SP - 75 UR - https://m2.mtmt.hu/api/publication/31642870 ID - 31642870 LA - English DB - MTMT ER - TY - CHAP AU - Tóth, Gábor AU - Bozsó, Zsolt AU - Szolomájer, János AU - Kele, Zoltán AU - Zoltán, Pethő AU - János, Almássy AU - Zoltán, Varga ED - Rakonczay, Zoltán ED - Kiss, Lóránd TI - Synthesis of ryanodine receptor selective charybdotoxin analogues T2 - Proceedings of the EFOP-3.6.2-16-2017-00006 (LIVE LONGER) project PB - University of Szeged CY - Szeged SN - 9789633067642 PY - 2020 SP - 74 UR - https://m2.mtmt.hu/api/publication/31642862 ID - 31642862 LA - English DB - MTMT ER - TY - JOUR AU - Jenei, Sándor AU - Tiricz, Hilda AU - Szolomájer, János AU - Tímár, Edit AU - Klement, Éva AU - Al Bouni, Mohamad Anas AU - Lima, Rui AU - Kata, Diána AU - Harmati, Mária AU - Buzás, Krisztina AU - Földesi, Imre AU - Tóth, Gábor AU - Endre, Gabriella AU - Kondorosi, Éva TI - Potent Chimeric Antimicrobial Derivatives of the Medicago truncatula NCR247 Symbiotic Peptide JF - FRONTIERS IN MICROBIOLOGY J2 - FRONT MICROBIOL VL - 11 PY - 2020 PG - 10 SN - 1664-302X DO - 10.3389/fmicb.2020.00270 UR - https://m2.mtmt.hu/api/publication/31281264 ID - 31281264 N1 - Funding Agency and Grant Number: Hungarian National Office for Research, Development and Innovation (NKFIH) [GINOP 2.3.2-15-2016-00014 Evomer, GINOP 2.3.2-15-2016-00015 I-KOM, GINOP-2.3.2-15-2016-00001, GINOP-2.3.2-15-2016-00020]; ERCEuropean Research Council (ERC) [269067]; NKFIH Frontline Research project [KKP129924]; Balzan research grant; [TUDFO/47138-1/2019-ITM FIKP]; [20391-3/2018/FEKUSTRAT] Funding text: Research has been supported by the Hungarian National Office for Research, Development and Innovation (NKFIH) through the grants GINOP 2.3.2-15-2016-00014 Evomer and GINOP 2.3.2-15-2016-00015 I-KOM, GINOP-2.3.2-15-2016-00001, GINOP-2.3.2-15-2016-00020; and by the ERC Advanced Grant 269067 "SymBiotics," the NKFIH Frontline Research project KKP129924 and the Balzan research grant to EKo; as well as by grants TUDFO/47138-1/2019-ITM FIKP and 20391-3/2018/FEKUSTRAT to GT. Institute of Plant Biology, Biological Research Centre, Szeged, Hungary Department of Medical Chemistry, University of Szeged, Szeged, Hungary Institute of Biochemistry, Biological Research Centre, Szeged, Hungary Department of Laboratory Medicine, University of Szeged, Szeged, Hungary Department of Oral Biology and Experimental Dental Research, University of Szeged, Szeged, Hungary MTA-SZTE Biomimetic Systems Research Group, University of Szeged, Szeged, Hungary Cited By :2 Export Date: 9 February 2021 Correspondence Address: Endre, G.; Institute of Plant Biology, Hungary; email: endre.gabriella@brc.hu Institute of Plant Biology, Biological Research Centre, Szeged, Hungary Department of Medical Chemistry, University of Szeged, Szeged, Hungary Institute of Biochemistry, Biological Research Centre, Szeged, Hungary Department of Laboratory Medicine, University of Szeged, Szeged, Hungary Department of Oral Biology and Experimental Dental Research, University of Szeged, Szeged, Hungary MTA-SZTE Biomimetic Systems Research Group, University of Szeged, Szeged, Hungary Cited By :3 Export Date: 1 May 2021 Correspondence Address: Endre, G.; Institute of Plant Biology, Hungary; email: endre.gabriella@brc.hu AB - In Rhizobium-legume symbiosis, the bacteria are converted into nitrogen-fixing bacteroids. In many legume species, differentiation of the endosymbiotic bacteria is irreversible, culminating in definitive loss of their cell division ability. This terminal differentiation is mediated by plant peptides produced in the symbiotic cells. In Medicago truncatula more than similar to 700 nodule-specific cysteine-rich (NCR) peptides are involved in this process. We have shown previously that NCR247 and NCR335 have strong antimicrobial activity on various pathogenic bacteria and identified interaction of NCR247 with many bacterial proteins, including FtsZ and several ribosomal proteins, which prevent bacterial cell division and protein synthesis. In this study we designed and synthetized various derivatives of NCR247, including shorter fragments and various chimeric derivatives. The antimicrobial activity of these peptides was tested on the ESKAPE bacteria; Enterococcus faecalis, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, and Escherichia coli as a member of Enterobacteriaceae and in addition Listeria monocytogenes and Salmonella enterica. The 12 amino acid long C-terminal half of NCR247, NCR247C partially retained the antimicrobial activity and preserved the multitarget interactions with partners of NCR247. Nevertheless NCR247C became ineffective on S. aureus, P. aeruginosa, and L. monocytogenes. The chimeric derivatives obtained by fusion of NCR247C with other peptide fragments and particularly with a truncated mastoparan sequence significantly increased bactericidal activity and altered the antimicrobial spectrum. The minimal bactericidal concentration of the most potent derivatives was 1.6 mu M, which is remarkably lower than that of most classical antibiotics. The killing activity of the NCR247-based chimeric peptides was practically instant. Importantly, these peptides had no hemolytic activity or cytotoxicity on human cells. The properties of these NCR derivatives make them promising antimicrobials for clinical use. LA - English DB - MTMT ER - TY - JOUR AU - Zarándi, Márta AU - Szolomájer, János TI - Amino acids: Chemistry, diversity and physical properties JF - AMINO ACIDS PEPTIDES AND PROTEINS J2 - AMINO ACIDS PEPT PROTEIN VL - 42 PY - 2018 SP - 1 EP - 84 PG - 84 SN - 1361-5904 DO - 10.1039/9781788010627-00001 UR - https://m2.mtmt.hu/api/publication/31848285 ID - 31848285 AB - The occurrence, chemistry, resolution, and analysis of amino acids published in the literature from 2013 finished with the year of 2016 are reviewed in this Chapter which is arranged in sections similar to previous Volumes in this Specialist Periodical report. Scientific Papers published during 2013-2016 have been sourced mainly from the Web of Science databases and Pubmed on the internet and from scanning a selection of major journals. © 2018 The Royal Society of Chemistry. LA - English DB - MTMT ER - TY - JOUR AU - Fehér, Krisztina AU - Timári, István AU - Rákosi, Kinga AU - Szolomájer, János AU - Tóthné Illyés, Tünde Zita AU - Bartók, Ádám AU - Varga, Zoltán AU - Panyi, György AU - Tóth, Gábor AU - E Kövér, Katalin TI - Probing pattern and dynamics of disulfide bridges using synthesis and NMR of an ion channel blocker peptide toxin with multiple diselenide bonds JF - CHEMICAL SCIENCE J2 - CHEM SCI VL - 7 PY - 2016 IS - 4 SP - 2666 EP - 2673 PG - 8 SN - 2041-6520 DO - 10.1039/C5SC03995A UR - https://m2.mtmt.hu/api/publication/2989146 ID - 2989146 N1 - Megjegyzés-27382737 OA gold AB - Anuroctoxin (AnTx), a 35-amino-acid scorpion toxin contg. four disulfide bridges, is a high affinity blocker of the voltage-gated potassium channel Kv1.3, but also blocks Kv1.2. To improve the potential therapeutic use of the toxin, we have designed a double substituted analog, [N17A/F32T]-AnTx, which showed comparable Kv1.3 affinity to the wild-type peptide, but 2500-fold increase in the selectivity for Kv1.3 over Kv1.2. In the present study we have achieved the chem. synthesis of a Sec-analog in which all cysteine (Cys) residues have been replaced by selenocysteine (Sec) forming four diselenide bonds. To the best of our knowledge this is the first time to replace, by chem. synthesis, all disulfide bonds with isosteric diselenides in a peptide/protein. Gratifyingly, the key pharmacol. properties of the Sec-[N17A/F32T]-AnTx are retained since the peptide is functionally active. We also propose here a combined exptl. and theor. approach including NOE- and 77Se-based NMR supplemented by MD simulations for conformational and dynamic characterization of the Sec-[N17A/F32T]-AnTx. The use of such combined approach allowed us to attain unequivocal assignment of all four diselenide bonds and supplemental MD simulations allowed to characterize the conformational dynamics around each disulfide/diselenide bridge. [on SciFinder(R)] LA - English DB - MTMT ER - TY - JOUR AU - Csapó, Edit AU - Bogár, Ferenc AU - Juhász, Ádám AU - Sebők, Dániel AU - Szolomájer, János AU - Tóth, Gábor AU - Majláth, Zsófia AU - Vécsei, László AU - Dékány, Imre TI - Determination of binding capacity and adsorption enthalpy between Human Glutamate Receptor (GluR1) peptide fragments and kynurenic acid by surface plasmon resonance experiments. Part 2: Interaction of GluR1270–300 with KYNA JF - COLLOIDS AND SURFACES B: BIOINTERFACES J2 - COLLOID SURFACE B VL - 133 PY - 2015 SP - 66 EP - 72 PG - 7 SN - 0927-7765 DO - 10.1016/j.colsurfb.2015.04.044 UR - https://m2.mtmt.hu/api/publication/2908470 ID - 2908470 N1 - Funding Agency and Grant Number: European Union; State of Hungary; European Social Fund [TAMOP-4.2.2.A-11/1/KONV-2012-0047]; Hungarian Brain Research Program (NAP) [KTIA-13-NAP-AIII/9]; EUROHEADPAIN [602633]\n Funding text: This research was supported by the European Union and the State of Hungary, co-financed by the European Social Fund in the framework of TAMOP-4.2.2.A-11/1/KONV-2012-0047, by the Hungarian Brain Research Program (NAP. Grant No. KTIA-13-NAP-AIII/9) and by EUROHEADPAIN (FP7-Health 2013-Innovation; Grant No. 602633). The authors thank Judit Kopniczky and Viktoria Hornok (University of Szeged) for the AFM measurements.\n CAplus AN 2015:1013556; MEDLINE PMID: 26087390 (Journal; Article; Research Support, Non-U.S. Gov't); AB - Abstract In the course of our previous work, the interactions of two peptide fragments (GluR1201–230 and GluR1231–259) of human glutamate receptor (GluR1201–300) polypeptide with kynurenic acid (KYNA) were investigated by surface plasmon resonance (SPR) spectroscopy. Besides quantitation of the interactions, the enthalpies of binding of KYNA on certain peptide fragment-modified gold surfaces were also reported. In the present work, a third peptide fragment (GluR1270–300) of the glutamate receptor was synthesized and its interaction with KYNA was investigated by an SPR technique. This 31-membered peptide was chemically bonded onto a gold-coated SPR chip via a cysteine residue. The peptide-functionalized biosensor chip was analyzed by atomic force microscopy (AFM) and theoretical calculations were performed on the structure and dimensions of the peptide on the gold surface. In order to determine the isosteric heat of adsorption of the binding of KYNA on the peptide-functionalized gold thin film, SPR experiments were carried out between +10 °C and +40 °C. The results on the GluR1270–300–KYNA system were compared with the previously published binding parameters of the interactions of GluR1201–230 and GluR1231–259 with KYNA. The binding abilities of KYNA with all three peptide fragments immobilized on the gold surface were estimated by a molecular docking procedure and the binding free energies of these AMPA receptor subunits with KYNA were determined. LA - English DB - MTMT ER - TY - CHAP AU - Paragi, Gábor AU - Bodnár, Brigitta AU - Szolomájer, János AU - Batta, Gyula AU - Bényei, Attila AU - Kele, Zoltán AU - Kupihár, Zoltán AU - Célia, Fonseca Guerra AU - F., Matthias Bickelhaupt AU - Artur, Ciesielski AU - Sebastien, Haar AU - Paolo, Samori AU - Stefano, Masiero AU - Gian, Piero Spada AU - Kovács, Lajos ED - Szigeti, Gyula Péter TI - Szupramolekuláris rendszerek purinokból T2 - Értékteremtés és értékközvetítés PB - Magyar Tudományos Akadémia (MTA) CY - Budapest SN - 9789635087990 PY - 2015 SP - 179 EP - 185 PG - 7 UR - https://m2.mtmt.hu/api/publication/2875728 ID - 2875728 LA - Hungarian DB - MTMT ER - TY - JOUR AU - Artur, Ciesielski AU - Sebastien, Haar AU - Bényei, Attila Csaba AU - Paragi, Gábor AU - Célia, Fonseca Guerra AU - F., Matthias Bickelhaupt AU - Stefano, Masiero AU - Szolomájer, János AU - Paolo, Samori AU - Gian, Piero Spada AU - Kovács, Lajos TI - Self-assembly of N3-substituted xanthines in the solid state and at a solid-liquid interface JF - LANGMUIR J2 - LANGMUIR VL - 29 PY - 2013 IS - 24 SP - 7283 EP - 7290 PG - 8 SN - 0743-7463 DO - 10.1021/la304540b UR - https://m2.mtmt.hu/api/publication/2155750 ID - 2155750 AB - Self-assembly of small molecular modules interacting through non-covalent forces is increasingly being used to generate functional structures and materials for electronic, catalytic, and biomedical applications. The greatest control over the geometry in H-bond supramolecular architectures, especially in H-bonded supramolecular polymers, can be achieved by exploiting the rich programmability of artificial nucleobases undergoing self-assembly through strong H-bonds. Here N3-functionalized xanthine modules are described, which are capable of self-associating through self-complementary H-bonding patterns to form H-bonded supramolecular ribbons. The self-association of xanthines through directional H-bonding between neighboring molecules allows the controlled generation of highly compact 1D supramolecular polymeric ribbons on graphite. These architectures have been characterized by scanning tunneling microscopy at a solid–liquid interface, corroborated by dispersion-corrected density functional theory (DFT) studies and X-ray diffraction. LA - English DB - MTMT ER - TY - GEN AU - Bodnár, Brigitta AU - Szolomájer, János AU - Paragi, Gábor AU - Kupihár, Zoltán AU - Kele, Zoltán AU - Artur, Ciesielski AU - Sebastien, Haar AU - Paolo, Samori AU - Stefano, Masiero AU - Gian, Piero Spada AU - Célia, Fonseca Guerra AU - F., Matthias Bickelhaupt AU - Kovács, Lajos TI - 3-Alkyl- and 3-glycosylxanthines: syntheses and behaviour in gas and liquid states and at a solid-liquid interface PY - 2013 UR - https://m2.mtmt.hu/api/publication/2332088 ID - 2332088 N1 - Admin láttamozta: 0 Jelleg: Tudományos Együttműködés: Nemzetközi Rekord létrehozás dátuma: 2013-06-10 14:11:28 Törölt: 0 Tipus: Egyéb konferenciakötet Nyelv: Angol és magyar Megjelenési forma: Nyomtatott kötet Adatgazda: Kovács Lajos (Nukleinsavak) Forrás: kézi felvitel Forrás éve: 2013 Állapot: jóváhagyva Hozzáférés: 0 Cím: MTA Szénhidrát, Nukleinsav és Antibiotikum Munkabizottság Ülése Év: 2013 Város: Mátrafüred Ország: Magyarország Befejező dátum: 2013-05-24 Kezdő dátum: 2013-05-22 LA - English DB - MTMT ER - TY - CHAP AU - Paragi, Gábor AU - Szolomájer, János AU - Kupihár, Zoltán AU - Batta, Gyula AU - Kele, Zoltán AU - Pádár, Petra AU - Penke, Botond AU - Zijlstra, Hester AU - Fonseca Guerra, Célia AU - Bickelhaupt, F.M AU - Kovács, Lajos ED - Wolfgang, Fritzsche ED - Lea, Spindler TI - Guanine, xanthine and uric acid assemblies: comparative theoretical and experimental studies T2 - Guanine quartets: structure and application PB - Royal Society of Chemistry (RSC) CY - Cambridge SN - 9781849734608 PY - 2013 SP - 179 EP - 193 PG - 15 DO - 10.1039/9781849736954-00179 UR - https://m2.mtmt.hu/api/publication/2016537 ID - 2016537 AB - Proceeding from promising dimer calculations, tetramer and quadruplex assemblies of 9-methylxanthine and 9-methyluric acid have been investigated by quantum-chemical calculations. In the gas phase, the new structures are less stable than the guanine tetrad as a consequence of the absence of a cooperative effect in the former and its presence in the latter. The lack of cooperativity in the new structures can be only partly compensated by strong low-barrier hydrogen bonds (LBHB). Moreover, the new tetramers are positively charged and probably can exist only in the presence of ions. Similar calculations suggest that 3-methylxanthine (3MX) is a good candidate for tetrad and quadruplex structures and the existence of (3MX)n  cat+ aggregates (n = 4, 8; cat+ = NH4+, Na+, K+) has been experimentally observed in the gas phase through mass spectrometry (MS) measurements. Detailed NMR studies in solution have also verified that the „internal” H-bonds (N1H...O6) in the (3MX)4 structures must be stronger than the „external” H-bonds (N7H...O2). In general, we found that guanine quartets (G4) are still more strongly bound than xanthine quartets (X4), despite the fact that they have the same number of hydrogen bonds. This is due to a cooperativity effect in the former case, as follows from our computational analyses. This is true not only in the gas phase but also in telomere-like structures where the quartet coordinates to two sodium ions and this complex is stacked in between two other quartets. In aqueous solution and in the absence of stacking quartet partners, however, the cooperativity is quenched and G4 and X4 are equally strongly bound. LA - English DB - MTMT ER - TY - CONF AU - Bényei, Attila AU - Szolomájer, János AU - Paragi, Gábor AU - Fonseca Guerra, Célia AU - Bickelhaupt, F Matthias AU - Kupihár, Zoltán AU - Batta, Gyula AU - Ciesielski, Artur AU - Haar, Sebastien AU - Samori, Paolo AU - Spada, Gian Piero AU - Kovács, Lajos TI - Self-assembly of 3-substituted xanthines in solid phase and at solid-liquid interface T2 - Conformational diversity and applications of G-quadruplexes C1 - Barcelona PY - 2012 SP - 44 EP - 44 PG - 1 UR - https://m2.mtmt.hu/api/publication/2024988 ID - 2024988 AB - The self-assembly of guanine derivatives into tetrads and their stacks (quadruplex motifs) has long been known.1 In our previous studies, we have demonstrated that 3-methylxanthine with similar hydrogen bonding capacity forms tetrads and octads in gas and liquid phases in the presence of cations.2 As an extension to our findings, we have investigated the structure of 3-methyl- and 3-octadecylxanthines in solid state and at solid-liquid interface. The X-ray structure of 3-methylxanthine shows monomers that are bound by four hydrogen bonds to neighboring molecules resulting overall in a planar arrangement.3 A new X-ray study of a single crystal of 3-methylxanthine revealed, beyond the reported structure, also the presence of a new polymorph with monomers that are bound by only two hydrogen bonds (N1—H1•••N9 and N7—H7•••O2) to the other molecules in a nearly perpendicular arrangement. The need for exploring ordered architectures at the molecular scale has made scanning tunneling microscopy (STM) a widely employed yet extremely powerful tool to investigate supramolecular materials at interfaces with sub-molecular resolution. In the past we have shown the metal-templated reversible assembly/reassembly process of 9-octadecylguanine into highly ordered quartets and ribbons.4 Herein, we present a submolecular-resolution STM visualization of the self-assembly of two alkylated xanthine derivatives, i.e. 3-octadecyl- and 3-methylxanthine at the solid-liquid interface. In order to gain insight into the experimental self-assembly behavior of xanthines forming supramolecular H-bonded ribbons, we have performed computational modelling using high-level quantum chemical methods as well. LA - English DB - MTMT ER - TY - GEN AU - Bényei, Attila AU - Berkesi, Ottó AU - Szolomájer, János AU - Paragi, Gábor AU - Kupihár, Zoltán AU - Batta, Gyula AU - Artur, Ciesielski AU - Sebastien, Haar AU - Paolo, Samori AU - Gian, Piero Spada AU - Kovács, Lajos TI - 3-Szubsztituált xantinok szerkezete gáz, folyadék, szilárd fázisban és folyadék-szilárd határfelületen PY - 2012 UR - https://m2.mtmt.hu/api/publication/2016589 ID - 2016589 N1 - ElőadásAdmin láttamozta: 0 Jelleg: Tudományos Együttműködés: Hazai Rekord létrehozás dátuma: 2012-07-10 15:37:28 Törölt: 0 Tipus: Egyéb konferenciakötet Nyelv: Magyar Adatgazda: Kovács Lajos (Nukleinsavak) Forrás: kézi felvitel Forrás éve: 2012 Állapot: feldolgozás alatt Hozzáférés: 0 Cím: MTA Szénhidrát, Nukleinsav és Antibiotikum Munkabizottsága tudományos ülése Év: 2012 Város: Debrecen Ország: Magyarország Befejező dátum: 2012-06-01 Kiadás helye: Debrecen Kezdő dátum: 2012-05-31 LA - Hungarian DB - MTMT ER - TY - JOUR AU - Bokros, Attila AU - Bánfi, Annamária AU - Kupihár, Zoltán AU - Kele, Zoltán AU - Tóthné Illyés, Tünde Zita AU - Szolomájer, János AU - Kovács, Lajos TI - Electrospray Ionization Mass Spectrometric Analysis of Highly Reactive Glycosyl Halides JF - MOLECULES J2 - MOLECULES VL - 17 PY - 2012 IS - 7 SP - 8351 EP - 8358 PG - 8 SN - 1420-3049 DO - 10.3390/molecules17078351 UR - https://m2.mtmt.hu/api/publication/2015022 ID - 2015022 AB - Highly reactive glycosyl chlorides and bromides have been analysed by a routine mass spectrometric method using electrospray ionization and lithium salt adduct-forming agents in anhydrous acetonitrile solution, providing salient lithiated molecular ions [M+Li]+, [2M+Li]+ etc. The role of other adduct-forming salts has also been evaluated. The lithium salt method is useful for accurate mass determination of these highly sensitive compounds. LA - English DB - MTMT ER - TY - JOUR AU - Paragi, Gábor AU - Szolomájer, János AU - Batta, Gyula AU - Kele, Zoltán AU - Kupihár, Zoltán AU - Pádár, Petra AU - Célia, Fonseca Guerra AU - F., Matthias Bickelhaupt AU - Kovács, Lajos TI - Purinszármazékokból képződő szupramolekuláris rendszerek JF - MAGYAR KÉMIKUSOK LAPJA J2 - MAGY KEM LAP VL - 67 PY - 2012 IS - 3 SP - 88 EP - 89 PG - 2 SN - 0025-0163 UR - https://m2.mtmt.hu/api/publication/1840208 ID - 1840208 N1 - Teljes lapszám http://www.mkl.mke.org.hu/images/stories/downloads/2012/2012_3.pdf LA - Hungarian DB - MTMT ER -