TY - JOUR AU - Béres, Kende Attila AU - Dürvanger, Zsolt AU - Homonnay, Zoltán AU - Nagyné Bereczki, Laura AU - Barta Holló, Berta AU - Farkas, Attila AU - Petruševski, Vladimir M. AU - Kótai, László TI - Insight into the Structure and Redox Chemistry of [Carbonatotetraamminecobalt(III)] Permanganate and Its Monohydrate as Co-Mn-Oxide Catalyst Precursors of the Fischer-Tropsch Synthesis JF - INORGANICS J2 - INORGANICS VL - 12 PY - 2024 IS - 4 SP - 94 SN - 2304-6740 DO - 10.3390/inorganics12040094 UR - https://m2.mtmt.hu/api/publication/34753165 ID - 34753165 AB - [Carbonatotetraamminecobalt(III)] permanganate monohydrate was synthesized first in the metathesis reaction of [Co(NH3)4CO3]NO3 and NaMnO4 in aqueous solution. Its thermal dehydration at 100 °C resulted in phase-pure [Co(NH3)4CO3]MnO4 (compound 1). Compounds 1 and 2 (i.e., the hydrated form) were studied with IR, far-IR, and low-temperature Raman spectroscopies, and their vibrational modes were assigned. The lattice parameters were determined by powder X-ray diffraction (PXRD) and single crystal X-ray diffraction (SXRD) methods for the triclinic and orthorhombic compounds 1 and 2, respectively. The detailed structure of compound 2 was determined, and the role of hydrogen bonds in the structural motifs was clarified. UV studies on compounds 1 and 2 showed the distortion of the octahedral geometry of the complex cation during dehydration because of the partial loss of the hydrogen bonds between the crystal water and the ligands of the complex cation. The thermal decomposition consists of a solid phase quasi-intramolecular redox reaction between the ammonia ligands and permanganate anions with the formation of ammonia oxidation products (H2O, NO, N2O, and CO2). The solid phase reaction product is amorphous cobalt manganese oxide containing ammonium, carbonate (and nitrate) anions. The temperature-controlled thermal decomposition of compound 2 in toluene at 110 °C showed that one of the decomposition intermediates is ammonium nitrate. The decomposition intermediates are transformed into Co1.5Mn1.5O4 spinel with MnCo2O4 structure upon further heating. Solid compound 2 gave the spinel at 500 °C both in an inert and air atmosphere, whereas the sample pre-treated in toluene at 110 °C without and with the removal of ammonium nitrate by aqueous washing, gave the spinel already at 300 and 400 °C, respectively. The molten NH4NO3 is a medium to start spinel crystallization, but its decomposition stops further crystal growth of the spinel phase. By this procedure, the particle size of the spinel product as low as ~4.0 nm could be achieved for the treatments at 300 and 400 °C, and it increased only to 5.7 nm at 500 °C. The nano-sized mixed cobalt manganese oxides are potential candidates as Fischer-Tropsch catalysts. LA - English DB - MTMT ER - TY - THES AU - Dürvanger, Zsolt TI - Molekuláris felismerés vizsgálata fehérje - peptid komplexek körében PB - Eötvös Loránd Tudományegyetem (ELTE) PY - 2023 SP - 110 UR - https://m2.mtmt.hu/api/publication/34784970 ID - 34784970 LA - Hungarian DB - MTMT ER - TY - JOUR AU - Horváth, Dániel AU - Dürvanger, Zsolt AU - Karancsiné Menyhárd, Dóra AU - Sulyok-Eiler, Máté AU - Bencs, Fruzsina AU - Gyulai, Gergő AU - Horváth, Péter AU - Taricska, Nóra AU - Perczel, András TI - Polymorphic amyloid nanostructures of hormone peptides involved in glucose homeostasis display reversible amyloid formation JF - NATURE COMMUNICATIONS J2 - NAT COMMUN VL - 14 PY - 2023 IS - 1 PG - 15 SN - 2041-1723 DO - 10.1038/s41467-023-40294-x UR - https://m2.mtmt.hu/api/publication/34084209 ID - 34084209 N1 - ELKH-ELTE Protein Modeling Research Group ELTE Eötvös Loránd University, Pázmány Péter sétány 1/A, Budapest, H-1117, Hungary Laboratory of Structural Chemistry and Biology ELTE Eötvös Loránd University, Pázmány Péter sétány 1/A, Budapest, H-1117, Hungary Hevesy György PhD School of Chemistry, ELTE Eötvös Loránd University, Pázmány Péter sétány 1/A, Budapest, H-1117, Hungary Laboratory of Interfaces and Nanostructures, Institute of Chemistry, Eötvös Loránd University, Pázmány Péter sétány 1/A, Budapest, H-1117, Hungary Department of Pharmaceutical Chemistry, Semmelweis University, Hőgyes Endre utca 9, Budapest, 1092, Hungary Export Date: 2 October 2023 Correspondence Address: Perczel, A.; ELKH-ELTE Protein Modeling Research Group ELTE Eötvös Loránd University, Pázmány Péter sétány 1/A, Hungary; email: perczel.andras@ttk.elte.hu AB - A large group of hormones are stored as amyloid fibrils in acidic secretion vesicles before they are released into the bloodstream and readopt their functional state. Here, we identify an evolutionarily conserved hexapeptide sequence as the major aggregation-prone region (APR) of gastrointestinal peptides of the glucagon family: xFxxWL. We determine nine polymorphic crystal structures of the APR segments of glucagon-like peptides 1 and 2, and exendin and its derivatives. We follow amyloid formation by CD, FTIR, ThT assays, and AFM. We propose that the pH-dependent changes of the protonation states of glutamate/aspartate residues of APRs initiate switching between the amyloid and the folded, monomeric forms of the hormones. We find that pH sensitivity diminishes in the absence of acidic gatekeepers and amyloid formation progresses over a broad pH range. Our results highlight the dual role of short aggregation core motifs in reversible amyloid formation and receptor binding. LA - English DB - MTMT ER - TY - JOUR AU - Béres, Kende Attila AU - Homonnay, Zoltán AU - Nagyné Bereczki, Laura AU - Dürvanger, Zsolt AU - Petruševski, Vladimir M. AU - Farkas, Attila AU - Kótai, László TI - Crystal Nanoarchitectonics and Characterization of the Octahedral Iron(III)–Nitrate Complexes with Isomer Dimethylurea Ligands JF - CRYSTALS J2 - CRYSTALS VL - 13 PY - 2023 IS - 7 PG - 20 SN - 2073-4352 DO - 10.3390/cryst13071019 UR - https://m2.mtmt.hu/api/publication/34037505 ID - 34037505 N1 - Institute of Materials and Environmental Chemistry, Research Centre for Natural Sciences, Budapest, H-1117, Hungary György Hevesy PhD School of Chemistry, ELTE Eötvös Loránd University, Budapest, H-1117, Hungary Institute of Chemistry, ELTE Eötvös Loránd University, Budapest, H-1117, Hungary Centre for Structural Science, Research Centre for Natural Sciences, Budapest, H-1117, Hungary ELKH-ELTE Protein Modelling Research Group, Budapest, H-1117, Hungary Structural Chemistry and Biology Laboratory, Institute of Chemistry, ELTE Eötvös Loránd University, Budapest, H-1117, Hungary Faculty of Natural Sciences and Mathematics, Ss. Cyril and Methodius University, Skopje, MK-1000, North Macedonia Department of Organic Chemistry and Technology, Faculty of Chemical Technology and Biotechnology, Budapest University of Technology and Economics, Budapest, H-1111, Hungary Deuton-X Ltd, Érd, H-2030, Hungary Export Date: 14 August 2023 Correspondence Address: Kótai, L.; Institute of Materials and Environmental Chemistry, Hungary; email: kotai.laszlo@ttk.hu AB - Three octahedral iron(III) nitrate complexes with dimethylated urea ligand isomers, [hexakis(N,N’-dimethylurea-O)iron(III)] nitrate (compound 1), trans-[diaquatetrakis(N,N-dimethylurea-O)iron(III)] nitrate (compound 2), and [hexakis(N,N-dimethylurea-O)iron(III)] nitrate trihydrate (compound 3) were prepared and characterized with single crystal X-ray diffraction, IR, Raman and UV–Vis methods. In compounds 1 and 3, six dimethylurea ligands coordinate to the central FeIII ion via the oxygen in octahedral geometry and the ligands are arranged in a propeller-like manner, dividing the complex cations into two sides. In compound 1, the dimethylurea propellers screw in the opposite direction on the two sides of the complex and in compound 3, they are arranged with the same handedness on the two sides. The complexes have helical chirality. The two sides of the complex cations differ not only in the rotation direction of the ligands but also in the hydrogen bond formation. On one side of the complex cation, the ligands form intermolecular hydrogen bonds only with the crystal waters, meanwhile on the other side of the complex, the ligands form hydrogen bonds only with the nitrate ions. In compound 2, [Fe(N,N-dimethylurea)4(H2O)2]3+ cations form layers that are separated by interconnected NO3− ions forming a hydrogen bonding system and connecting the complex cations A-s and B-s. The three crystallographically different nitrate ions each form four hydrogen bonds in a way that they have one bidentate O atom and two monodentate O atoms; however, the anions differ in their hydrogen bonding. The spectroscopic characteristics of compound 2 were determined by IR measurements on the deuterated compound 2 as well. LA - English DB - MTMT ER - TY - JOUR AU - Dürvanger, Zsolt AU - Juhász, Tünde AU - Liliom, Károly AU - Harmat, Veronika TI - Structures of calmodulin-melittin complexes show multiple binding modes lacking classical anchoring interactions JF - JOURNAL OF BIOLOGICAL CHEMISTRY J2 - J BIOL CHEM VL - 299 PY - 2023 IS - 4 PG - 15 SN - 0021-9258 DO - 10.1016/j.jbc.2023.104596 UR - https://m2.mtmt.hu/api/publication/33696970 ID - 33696970 N1 - Export Date: 2 June 2023 CODEN: JBCHA Correspondence Address: Harmat, V.; Laboratory of Structural Chemistry and Biology, Hungary; email: veronika.harmat@ttk.elte.hu AB - Calmodulin (CaM) is a Ca2+ sensor protein found in all eukaryotic cells that regulates a large number of target proteins in a Ca2+ concentration-dependent manner. As a transient type hub protein, it recognizes linear motifs of its targets, though for the Ca2+-dependent binding no consensus sequence was identified. Its complex with melittin, a major component of bee venom, is often used as a model system of protein - protein complexes. Yet, the structural aspects of the binding are not well understood, as only diverse, low-resolution data are available concerning the association. We present the crystal structure of melittin in complex with Ca2+-saturated calmodulins from two, evolutionarily distant species, Homo sapiens and Plasmodium falciparum representing three binding modes of the peptide. Results - augmented by molecular dynamics simulations - indicate that multiple binding modes can exist for CaM-melittin complexes, as an intrinsic characteristic of the binding. While the helical structure of melittin remains, swapping of its salt bridges and partial unfolding of its C-terminal segment can occur. In contrast to the classical way of target recognition by CaM, we found that different sets of residues can anchor at the hydrophobic pockets of CaM, which were considered as main recognition sites. Finally, the nanomolar binding affinity of the CaM-melittin complex is created by an ensemble of arrangements of similar stability - tight binding is achieved not by optimized specific interactions but by simultaneously satisfying less optimal interaction patterns in co-existing different conformers. LA - English DB - MTMT ER - TY - JOUR AU - Béres, Kende Attila AU - Homonnay, Zoltán AU - Barta Holló, B. AU - Gracheva, Maria AU - Petruševski, V.M. AU - Farkas, Attila AU - Dürvanger, Zsolt AU - Kótai, László TI - Synthesis, structure, and Mössbauer spectroscopic studies on the heat-induced solid-phase redox reactions of hexakis(urea-O)iron(III) peroxodisulfate JF - JOURNAL OF MATERIALS RESEARCH J2 - J MATER RES VL - 38 PY - 2023 SP - 1102 EP - 1118 PG - 17 SN - 0884-2914 DO - 10.1557/s43578-022-00794-w UR - https://m2.mtmt.hu/api/publication/33628427 ID - 33628427 AB - Anhydrous hexakis(urea-O)iron(III)]peroxydisulfate ([Fe(urea-O) 6 ] 2 (S 2 O 8 ) 3 (compound 1 ), and its deuterated form were prepared and characterized with single-crystal X-ray diffraction and spectroscopic (IR, Raman, UV, and Mössbauer) methods. Six crystallographically different urea ligands coordinate via their oxygen in a propeller-like arrangement to iron(III) forming a distorted octahedral complex cation. The octahedral arrangement of the complex cation and its packing with two crystallographically different persulfate anions is stabilized by extended intramolecular (N–H⋯O = C) and intermolecular (N–H⋯O–S) hydrogen bonds. The two types of peroxydisulfate anions form different kinds and numbers of hydrogen bonds with the neighboring [hexakis(urea-O) 6 iron(III)] 3+ cations. There are spectroscopically six kinds of urea and three kinds (2 + 1) of persulfate ions in compound 1 , thus to distinguish the overlapping bands belonging to internal and external vibrational modes, deuteration of compound 1 and low-temperature Raman measurements were also carried out, and the bands belonging to the vibrational modes of urea and persulfate ions have been assigned. The thermal decomposition of compound 1 was followed by TG-MS and DSC methods in oxidative and inert atmospheres as well. The decomposition starts at 130 °C in inert atmosphere with oxidation of a small part of urea (~ 1 molecule), which supports the heat demand of the transformation of the remaining urea into ammonia and biuret/isocyanate. The next step of decomposition is the oxidation of ammonia into N 2 along with the formation of SO 2 (from sulfite). The main solid product proved to be (NH 4 ) 3 Fe(SO 4 ) 3 in air. In inert atmosphere, some iron(II) compound also formed. The thermal decomposition of (NH 4 ) 3 Fe(SO 4 ) 3 via NH 4 Fe(SO 4 ) 2 formation resulted in α -Fe 2 O 3 . The decomposition pathway of NH 4 Fe(SO 4 ) 2 , however, depends on the experimental conditions. NH 4 Fe(SO 4 ) 2 transforms into Fe 2 (SO 4 ) 3 , N 2 , H 2 O, and SO 2 at 400 °C, thus the precursor of α -Fe 2 O 3 is Fe 2 (SO 4 ) 3 . Above 400 °C (at isotherm heating), however, the reduction of iron(III) centers was also observed. FeSO 4 formed in 27 and 75% at 420 and 490 °C, respectively. FeSO 4 also turns into α -Fe 2 O 3 and SO 2 on further heating. LA - English DB - MTMT ER - TY - JOUR AU - Béres, Kende Attila AU - Szilágyi, Fanni AU - Homonnay, Zoltán AU - Dürvanger, Zsolt AU - Nagyné Bereczki, Laura AU - Trif, László AU - Petruševski, Vladimir M. AU - Farkas, Attila AU - Bayat, Niloofar AU - Kótai, László TI - Structural, Spectroscopic, and Thermal Decomposition Features of [Carbonatotetraamminecobalt(III)] Iodide—Insight into the Simultaneous Solid-Phase Quasi-Intramolecular Redox Reactions JF - INORGANICS J2 - INORGANICS VL - 11 PY - 2023 IS - 2 PG - 21 SN - 2304-6740 DO - 10.3390/inorganics11020068 UR - https://m2.mtmt.hu/api/publication/33610854 ID - 33610854 N1 - Correspondence Address: Béres, K.A.; Research Centre for Natural Sciences, Magyar Tudósok krt. 2, Hungary; email: beres.kende.attila@ttk.hu Correspondence Address: Kótai, L.; Research Centre for Natural Sciences, Magyar Tudósok krt. 2, Hungary; email: kotai.laszlo@ttk.hu AB - [κ2-O,O′-Carbonatotetraamminecobalt(III)] iodide, or [Co(NH3)4CO3]I, named in this paper as compound 1, was prepared and characterized comprehensively with spectroscopic (IR, Raman and UV) and single-crystal X-ray diffraction methods. Compound 1 was orthorhombic, and isomorphous with the analogous bromide. The four ammonia ligands and the carbonate anion were coordinated to the central cobalt cation in a distorted octahedral geometry. The carbonate ion formed a four-membered symmetric planar chelate ring. The complex cations were bound to each other by N-H···O hydrogen bonds and formed zigzag sheets via an extended 2D hydrogen bond network. The complex cations and iodide ions were arranged into ion pairs and each cation bound its iodide pair through three hydrogen bonds. The thermal decomposition started with the oxidation of the iodide ion by CoIII in the solid phase resulting in [Co(NH3)4CO3] and I2. This intermediate CoII-complex in situ decomposed into Co3O4 and C-N bond containing intermediates. In inert atmosphere, CO or C-N bond containing compounds, and also, due to the in situ decomposition of CoCO3 intermediate, Co3O4 was formed. The quasi-intramolecular solid-phase redox reaction of [Co(NH3)4CO3] might have resulted in the formation of C-N bond containing compounds with substoichiometric release of ammonia and CO2 from compound 1. The C-N bond containing intermediates reduced Co3O4 into CoO and Co, whereas in oxygen-containing atmosphere, the end-product was Co3O4, even at 200 °C, and the endothermic ligand loss reaction coincided with the consecutive exothermic oxidation processes. LA - English DB - MTMT ER - TY - JOUR AU - Béres, Kende Attila AU - Homonnay, Zoltán AU - Kvitek, L AU - Dürvanger, Zsolt AU - Kubikova, M AU - Harmat, Veronika AU - Szilágyi, F AU - Czégény, Zsuzsanna AU - Németh, Péter AU - Nagyné Bereczki, Laura AU - Petruševski, VM. AU - Pápai, Mátyás Imre AU - Farkas, Attila AU - Kótai, László TI - Thermally Induced Solid-Phase Quasi-Intramolecular Redox Reactions of [Hexakis(urea-O)iron(III)] Permanganate: An Easy Reaction Route to Prepare Potential (Fe,Mn)O x Catalysts for CO2 Hydrogenation JF - INORGANIC CHEMISTRY J2 - INORG CHEM VL - 61 PY - 2022 IS - 36 SP - 14403 EP - 14418 PG - 16 SN - 0020-1669 DO - 10.1021/acs.inorgchem.2c02265 UR - https://m2.mtmt.hu/api/publication/33076479 ID - 33076479 N1 - Institute of Materials and Environmental Chemistry, Research Centre for Natural Sciences, Magyar Tudósok krt. 2, Budapest, H-1117, Hungary György Hevesy PhD School of Chemistry, Institute of Chemistry, ELTE Eötvös Loránd University, Pázmány Péter s. 1/A, Budapest, H-1117, Hungary Faculty of Science, Department of Physical Chemistry, Palacky University Olomouc, 17. Listopadu 12, Olomouc, 77146, Czech Republic Structural Chemistry and Biology Laboratory, Institute of Chemistry, ELTE Eötvös Loránd University, Pázmány Péter s. 1/A, Budapest, H-1117, Hungary ELKH-ELTE Protein eModelling Research Group, Pázmány Péter s. 1/A, Budapest, H-1117, Hungary Bay Zoltan Ltd. for Applied Research, Production Division (BAY-PROD), 1 Kondorfa, Budapest, H-1116, Hungary Institute for Geological and Geochemical Research, Research Centre for Astronomy and Earth Sciences, ELKH, Budaörsi street 45, Budapest, H-1112, Hungary Faculty of Natural Sciences and Mathematics, Ss. Cyril and Methodius University, Skopje, MK-1000, North Macedonia Wigner Research Centre for Physics, P.O. Box 49, Budapest, H-1525, Hungary Department of Organic Chemistry, Budapest University of Technology and Economics, Müegyetem rakpart 3, Budapest, H-1111, Hungary Deuton-X Ltd., Selmeci u. 89, Érd, H-2030, Hungary Cited By :5 Export Date: 30 June 2023 CODEN: INOCA Correspondence Address: Kótai, L.; Institute of Materials and Environmental Chemistry, Magyar Tudósok krt. 2, Hungary; email: kotai.laszlo@ttk.hu LA - English DB - MTMT ER - TY - JOUR AU - Dürvanger, Zsolt AU - Boros, Eszter AU - Nagy, Zoltán Attila AU - Hegedüs, Rózsa AU - Megyeri, Márton AU - Dobó, József AU - Gál, Péter AU - Schlosser, Gitta (Vácziné) AU - Ángyán, Annamária F. AU - Gáspári, Zoltán AU - Perczel, András AU - Harmat, Veronika AU - Mező, Gábor AU - Karancsiné Menyhárd, Dóra AU - Pál, Gábor TI - Directed Evolution-Driven Increase of Structural Plasticity Is a Prerequisite for Binding the Complement Lectin Pathway Blocking MASP-Inhibitor Peptides JF - ACS CHEMICAL BIOLOGY J2 - ACS CHEM BIOL VL - 17 PY - 2022 IS - 4 SP - 969 EP - 986 PG - 18 SN - 1554-8929 DO - 10.1021/acschembio.2c00114 UR - https://m2.mtmt.hu/api/publication/32778843 ID - 32778843 N1 - Laboratory of Structural Chemistry and Biology, Institute of Chemistry, ELTE Eötvös Loránd University, Pázmány Péter sétány 1/A, Budapest, H-1117, Hungary Department of Biochemistry, ELTE Eötvös Loránd University, Pázmány Péter sétány 1/C, Budapest, H-1117, Hungary MTA-ELTE Research Group of Peptide Chemistry, Pázmány Péter sétány 1/A, Budapest, H-1117, Hungary Institute of Enzymology, Research Centre for Natural Sciences, Magyar tudósok krt 2, Budapest, H-1117, Hungary Department of Analytical Chemistry, MTA-ELTE Lendület Ion Mobility Mass Spectrometry Research Group, Institute of Chemistry, ELTE Eötvös Loránd University, Pázmány Péter sétány 1/A, Budapest, H-1117, Hungary Faculty of Information Technology and Bionics, Pázmány Péter Catholic University, Práter u. 50/A, Budapest, H-1083, Hungary MTA-ELTE Protein Modelling Research Group, Eötvös Loránd Research Network, Pázmány Péter sétány 1/A, Budapest, H-1117, Hungary Department of Organic Chemistry, ELTE Eötvös Loránd University, Pázmány Péter sétány 1/A, Budapest, H-1117, Hungary Export Date: 12 May 2022 CODEN: ACBCC Correspondence Address: Menyhárd, D.K.; Laboratory of Structural Chemistry and Biology, Pázmány Péter sétány 1/A, Hungary; email: dora.k.menyhard@ttk.elte.hu Correspondence Address: Pál, G.; Department of Biochemistry, Pázmány Péter sétány 1/C, Hungary; email: gabor.pal@ttk.elte.hu LA - English DB - MTMT ER - TY - JOUR AU - Nagyné Bereczki, Laura AU - Alexandre Fogaca, Lara AU - Dürvanger, Zsolt AU - Harmat, Veronika AU - Kamarás, Katalin AU - Németh, Gergely AU - Hollo, BB AU - Petrusevski, VM AU - Bódis, Eszter AU - Farkas, Attila AU - Szilágyi, Imre Miklós AU - Kótai, László TI - Dynamic disorder in the high-temperature polymorph of bis[diamminesilver(I)] sulfate-reasons and consequences of simultaneous ammonia release from two different polymorphs JF - JOURNAL OF COORDINATION CHEMISTRY J2 - J COORD CHEM VL - 74 PY - 2021 IS - 13 SP - 2144 EP - 2162 PG - 19 SN - 0095-8972 DO - 10.1080/00958972.2021.1953489 UR - https://m2.mtmt.hu/api/publication/32163599 ID - 32163599 N1 - Institute of Materials and Environmental Chemistry, Research Centre for Natural Sciences, ELKH, Budapest, Hungary Chemical Crystallography Research Laboratory, Research Centre for Natural Sciences, ELKH, Budapest, Hungary Department of Inorganic and Analytical Chemistry, Budapest University of Technology and Economics, Budapest, Hungary Laboratory of Structural Chemistry and Biology, Institute of Chemistry, ELTE Eötvös Loránd University, Budapest, Hungary MTA-ELTE Protein Modelling Research Group, Budapest, Hungary Institute for Solid State Physics and Optics, Wigner Research Centre for Physics, Budapest, Hungary Faculty of Sciences, University of Novi Sad, Novi Sad, Serbia Faculty of Natural Sciences and Mathematics, Ss. Cyryl and Methodius University, Skopje, North Macedonia Organic Chemistry Department, Budapest University of Technology and Economics, Budapest, Hungary Deuton-X Ltd, Érd, Hungary Cited By :7 Export Date: 11 April 2023 CODEN: JCCMB Correspondence Address: Kótai, L.; Institute of Materials and Environmental Chemistry, Hungary LA - English DB - MTMT ER -