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    Wyświetlanie 1-12 z 12
    Tytuł:
    Metalotioneiny i motywy policysteinylowe : oddziaływanie z jonami metali
    Metallothioneins and polythiol motifs : interactions with metal ions
    Autorzy:
    Krzywoszyńska, K.
    Kozłowski, H.
    Powiązania:
    https://bibliotekanauki.pl/articles/171939.pdf
    Data publikacji:
    2018
    Wydawca:
    Polskie Towarzystwo Chemiczne
    Tematy:
    metalotioneiny
    motywy policysteinylowe
    jony metali
    metallothioneins
    polythiol motifs
    metal ions
    Opis:
    Many of biochemical paths and processes require some metal ions to occur. There are also known the negative effects of the presence of metal ions in the organism. The both sides of metal ions interactions on the living organism require specific regulations and cannot be left without supervision and control of the organism itself. One of the strategy to keep the control on metal ions are cystein-rich proteins that play crucial role in detoxication of metal ions that are dangerous for human organism as well as they help to maintain homeostasis of essential metal ions. Matallothioneins are one of the well known, but still not fully understood, cysteine- rich proteins. They are small proteins but may contain up to 30% of cysteine residues in the sequence, and what makes them very special from chemical point of view - all of the thiols present there are reduced [1]. This property makes these proteins very tempting for coordination of various metal ions. The most efficient binding to metallothionein is observed for the ions belonging to a Group 11 and 12. Cu+, Zn2+ and Cd2+ represent these metal ions [2]. Besides of the lack of disulfide bridges, metallothioneins show also the absence or low amount of aromatic amino acid residues in the sequence [1]. Studies of the metallothioneins and their isoforms among different organisms show that the position of cysteine residues is very conservative [3]. Considering this aspect of metallothionein structure, some specific motifs of cysteine residues arrangement can be found in the sequence of these proteins. Most of the common polythiol motifs are CXC, CXXC, CXXXC, CC – where C is a cysteine residue and X is random α-amino acid residue (other than cysteine) [3–5]. The influence of the cysteine residues organization on the specificity of metal ions binding was intensively studied. The differences observed for specificity of metal ions binding by metallothioneins and selected polythiol motifs are reviewed in this paper – with strong emphasis on the effect of the cysteine residues topography.
    Źródło:
    Wiadomości Chemiczne; 2018, 72, 7-8; 383-395
    0043-5104
    2300-0295
    Pojawia się w:
    Wiadomości Chemiczne
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Regulacja aktywności katalitycznej rybozymów HDV oraz deoksyrybozymów za pomocą antybiotyków i jonów metali
    Regulation of the catalytic activity of HDV ribozymes and deoxyribozymes with antibiotics and metal ions
    Autorzy:
    Wrzesinski, J.
    Ciesiołka, J.
    Powiązania:
    https://bibliotekanauki.pl/articles/171740.pdf
    Data publikacji:
    2018
    Wydawca:
    Polskie Towarzystwo Chemiczne
    Tematy:
    antybiotyki
    rybozymy HDV
    deoksyrybozymy
    jony metali
    antibiotics
    HDV ribozymes
    deoxyribozymes
    metal ions
    Opis:
    This review article describes the results of a 15-year cooperation between the Department of RNA Biochemistry at the Institute of Bioorganic Chemistry, Polish Academy of Sciences in Poznań and the Medical Chemistry Team of the Faculty of Chemistry at the University of Wrocław, headed by Professor Małgorzata Jeżowska- -Bojczuk. A wide spectrum of antibiotics and other low molecular compounds and their complexes with Cu2+ ions have been tested as potential inhibitors of the HDV ribozyme catalytic reaction. Unexpectedly, it has been found that a number of compounds, depending on the conditions, exhibit inhibitory or stimulatory properties, i.e. they act as modulators of the RNA catalysis process. It was found that the effect of stimulation / inhibition of the catalytic activity of the HDV ribozyme is closely related to the degree of protonation of the antibiotics under study in given conditions. Their ability to inhibit catalysis also increases after binding the Cu2+ cation. In an environment with a higher pH, antibiotics usually stimulate the cleavage reaction, as at least some of their nitrogen centers are allowed to participate in the catalysis reaction, as proton acceptors / donors or a catalytic metal ion coordination site. During the study of one of the antibiotics, bacitracin, it was also observed that it exhibits nucleolytic properties with RNA and DNA molecules. The discovery of the hydrolytic properties of bacitracin extended the potential use of this antibiotic in antiviral therapy with the aim to destroy undesired nucleic acids in the cell. To search for DNAzymes catalyzing RNA hydrolysis, the in vitro selection method was used. In the selection experiment aimed at obtaining DNAzymes active in the presence of Cd2+ ions, variants belonging to the family of DNAzymes 8–17 previously described in the literature were obtained. Analysis of their properties showed that not only Cd2+ but also Zn2+ and Mn2+ ions support catalysis, therefore the site of catalytic metal ion coordination is not highly specific. The DNAzymes obtained in the second selection experiment showed an optimum of catalytic activity in the pH range of 4.0–4.5 and were inactive at a pH higher than 5.0. Interestingly, they do not require the presence of any divalent metal ions as cofactors in the catalysis reaction. The obtained results broaden the repertoire of DNAzymes which operate under non-physiological conditions and bring new information on the possible mechanisms of reactions catalyzed by nucleic acids.
    Źródło:
    Wiadomości Chemiczne; 2018, 72, 7-8; 397-415
    0043-5104
    2300-0295
    Pojawia się w:
    Wiadomości Chemiczne
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Polihistydylowe sekwencje z motywem His-tag – ich rola i biologiczne znaczenie oddziaływania z jonami metali
    Polyhistidine sequences with His-tag motif – their role and biological significance of interaction with metal ions
    Autorzy:
    Wątły, J.
    Kozłowski, H.
    Powiązania:
    https://bibliotekanauki.pl/articles/172145.pdf
    Data publikacji:
    2016
    Wydawca:
    Polskie Towarzystwo Chemiczne
    Tematy:
    histydyna
    His-tag
    jony metali
    białka
    histidine
    His-tag motif
    metal ions
    proteins
    Opis:
    His-tags are specific sequences containing six to nine subsequent histydyl residues and they are used commercially in immobilized metal affinity chromatography (IMAC) as molecular ‘anchors’ that bind to a metal ion (usually nickel), immobilized by chelation with nitrilotriacetic acid (NTA) bound to a solid support [37, 38]. Consecutive histidines are the common denominator for both His-tags used in molecular biology and for quite remote biological phenomena – more than 2000 histidine- rich proteins (HRPs) are found in microorganisms including 60% and 82% of archaeal and bacterial species, respectively and their roles are not well characterized [73]. The physicochemical properties of histidine make it a versatile amino acid that influences protein conformation and enzymatic activity [15]. Many natural proteins with a His-tag domain are assigned to different functions, for example: most bacterial proteins, containing this motif are probably involved in the homeostasis of nickel ions [68, 76], while others, e.g. newly isolated peptides from the venom of the snake genus Atheris contain poly-histidyl-poly-glycyl sequences (pHpG) can act on the cardiovascular system by inhibiting snake venom metalloproteinases and affect its function by acting on specific receptors [58, 62]. His-rich motifs have been found also e.g. in Zn2+ transporters, prion proteins, His-rich glycoproteins, transcription factors or numerous copper-binding proteins [56, 67, 84]. Binding mode and the thermodynamic properties of the system depends on the specific metal ion and the histidine sequence. Despite the wide application of the His-tag for purification of proteins, little is known about the properties of metalbinding to such tag domain. Recent experimental and theoretical studies have shown that metal ions, e.g. Cu2+ can bind to various sets of imidazoles depending on the number of histidine residues that are located in His-rich sequences. The occurrence of polymorphic binding states and the formation of an α-helical structure induced by metal ion coordination suggest that proteins with a His-tag domain may serve as the dynamic site able to ‘move’ metal ions along the tag sequence [99, 100]. This might explain the frequent occurrence of such sequences in bacterial Ni2+ chaperones, which transfer the metal ion between different proteins.
    Źródło:
    Wiadomości Chemiczne; 2016, 70, 11-12; 1-24
    0043-5104
    2300-0295
    Pojawia się w:
    Wiadomości Chemiczne
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Właściwości koordynacyjne wybranych cyklicznych hormonów peptydowych oraz ich pochodnych
    Coordination properties of selected cyclic peptide hormones and their analogues
    Autorzy:
    Witak, Weronika
    Marciniak, Aleksandra
    Powiązania:
    https://bibliotekanauki.pl/articles/1409943.pdf
    Data publikacji:
    2021
    Wydawca:
    Polskie Towarzystwo Chemiczne
    Tematy:
    hormony peptydowe
    peptydy
    wiązanie disulfidowe
    jony metali
    peptide hormones
    cyclic peptides
    disulfide bridge
    metal ions
    Opis:
    Hormones are a heterogeneous, significant compounds, responsible for proper functioning of living organisms, produced by specialized cells, tissues and glands. Theirs main role is signals transmission to target tissues, responsible for the right working of the whole organism. Dysfunctions of the hormones homeostasis balance lead to disease states [1-3]. Recently, scientists have paid attention to role of the metal ions in the proper synthesis of these compounds and functioning of human body [4]. More and more scientific works explain the complicated roles of metals as beneficial factors that stimulate the conformation of peptides. Metal ions are responsible for biological properties and influence of hormones binding to appropriate receptors, but also adverse factors [4,5]. The search for an answer to the question about the metal - hormone relationship has led to the development of a new, interdisciplinary studies: metalloendocrinology, linking inorganic chemistry with endocrinology [4]. In this work, we present the literature data that relate to metal - peptide hormone interactions. We focused on cyclic hormones with a disulfide bridge and their analogues. In our review we have focused on selected natural cyclic peptide hormones: oxytocin, vasopressin, somatostatin, hepcidin and amylin. The studies on the coordination abilities showed that transition metal ions, such as copper(II), zinc(II) or nickel(II), form stable complexes with described peptides. Metal ions actively participate in many phenomena. They have played role in the formation of amylin aggregates in patients with type 2 diabetes [6]. The high ability to copper(II) by hepcidin may have an effect on its homeostasis [7]. Stable complexes of oxytocin and vasopressin facilitate binding with appropriate receptors for these peptides [8].
    Źródło:
    Wiadomości Chemiczne; 2021, 75, 5-6; 799-821
    0043-5104
    2300-0295
    Pojawia się w:
    Wiadomości Chemiczne
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Kompleksy jonów metali d- i f-elektronowych z N-tlenkiem pirydyny i związkami pochodnymi : badania spektroskopowe
    Complexes of d- and f-metal ions with pyridine N-oxide and its derivatives: spectroscopic studies
    Autorzy:
    Hnatejko, Z.
    Powiązania:
    https://bibliotekanauki.pl/articles/171812.pdf
    Data publikacji:
    2011
    Wydawca:
    Polskie Towarzystwo Chemiczne
    Tematy:
    kompleksy jonów metali
    jony metali
    N-tlenki pirydyny
    spektroskopia
    complexes
    metal ions
    pyridine N-oxides
    spectroscopy
    Opis:
    This article reviews results of studies, collected in the literature, related to complexation abilities of pyridine N-oxides, including forms and properties of dand f-metal ion complexes with this group of ligands. In this paper the synthetic pathways of the ligands, based on an oxidation of the corresponding heterocyclic compounds are presented (Scheme 3) [2, 4, 5]. Substituted pyridine N-oxides form an interesting group of compounds, which have found numerous applications [296-299, 314-318]. They have been used in catalysis, crystal engineering, synthesis of coordination polymers, as well as drugs and components in pharmaceutical chemistry [300-309]. Some of them are useful in destroying of microorganisms and the HIV virus [277, 278, 303-307]. Moreover, they are important compounds in the thermal and photochemical oxidation processes [296-299]. The complexes of metal ions with the N-oxide ligands can be formed by binding an oxygen atom of the N›O group, and/or by binding the substituents present in the aromatic ring, e.g. oxygen atoms of carboxylic groups. The complexes can be obtained in monomeric [64, 159], dimeric [58] or polymeric forms [60, 153, 175]. The formation of polymeric forms is more effective when the distance between the positions of COOH and N›O groups in the aromatic ring increases [168]. Complexes of Ln3+ ions and particularly of Eu3+ with pyridine N-oxides are good luminescent materials, better than their heterocyclic counterparts [180, 211]. The emission intensity of europium ions in these systems depends on the efficiency of the LMCT (ligand-metal charge transfer) and LMET (ligand-metal energy transfer) transitions, as well as on electron-donor properties of the substituents present in the pyridine N-oxide ring [37, 132, 155]. A special role in the complexation of Ln3+ ions plays cryptands, which can encapsulate the metal ion. This process protects the metal ion from a penetration of its first coordination sphere by solvent molecules or counterions [245, 246]. The complexes of europium(III) with macromonocyclic, macrobicyclic and acyclic ligands, equipped with photoactive units such as pyridine N-oxide, 2,2'-bipyridine-N,N'-dioxide or 3,3'-biisoquinoline-2,2'-dioxide in solutions, solid states, and incorporated in a silicate matrices by sol-gel method, gained a lot of attention [247-274].
    Źródło:
    Wiadomości Chemiczne; 2011, 65, 5-6; 461-501
    0043-5104
    2300-0295
    Pojawia się w:
    Wiadomości Chemiczne
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Homeostaza jonów Zn(II) w chorobach infekcyjnych
    Homeostasis of Zn(II) ions in infectious diseases
    Autorzy:
    Błaszczok, Aneta
    Gumienna-Kontecka, Elżbieta
    Powiązania:
    https://bibliotekanauki.pl/articles/1413176.pdf
    Data publikacji:
    2021
    Wydawca:
    Polskie Towarzystwo Chemiczne
    Tematy:
    jony cynku
    homeostaza
    patogeny
    zatrucie
    sekwestracja
    układ odpornościowy
    zinc ions
    homeostasis
    pathogens
    intoxication
    sequestration
    immune system
    Opis:
    Zinc is an essential element for all living organisms, as it performs important functions in many biological processes; its presence was identified in over 300 enzymes. Due to the important functions it performs, living organisms have created mechanisms to maintain zinc ion homeostasis. In mammals, these mechanisms are also used to combat pathogens. Specialized immune cells are able to manipulate, in response to immune signals, intracellular and extracellular concentrations of zinc ions through metal-specific transporters and transfer proteins. These actions cause that the resulting environment becomes unfavourable for pathogens. The ability to rapidly regulate free zinc levels is critical to cytokine responses and the proliferation, and activation of cells belonging to the adaptive immune system.
    Źródło:
    Wiadomości Chemiczne; 2021, 75, 3-4; 271-291
    0043-5104
    2300-0295
    Pojawia się w:
    Wiadomości Chemiczne
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Elektroanaliza z wykorzystaniem granic fazowych typu ciecz-ciecz
    Liquid-liquid interface used for electroanalytical applications
    Autorzy:
    Półtorak, Łukasz
    Powiązania:
    https://bibliotekanauki.pl/articles/2200438.pdf
    Data publikacji:
    2022
    Wydawca:
    Polskie Towarzystwo Chemiczne
    Tematy:
    liquid-liquid interface
    voltammetry
    amines
    ions
    electroanalysis
    granica fazowa typu ciecz-ciecz
    woltamperometria
    aminy
    jony
    elektroanaliza
    Opis:
    This work is focused on the electroanalytical application of the system composed from two immiscible electrolyte solutions also known as the electrified liquid-liquid interface. The particular attention is given to the electroanalytical signals originating from the simple ion transfer reactions (transfer of ion either from the aqueous to the organic or from the organic to the aqueous phase) providing ionic currents that can be probed in a function of the applied potential. Advantages and limitations of the soft junctions are underlines and discussed based on the examples published in the literature. Finally, future directions are given further indicating the utility of the concerned platform for the electroanalytical applications.
    Źródło:
    Wiadomości Chemiczne; 2022, 76, 11-12; 841-860
    0043-5104
    2300-0295
    Pojawia się w:
    Wiadomości Chemiczne
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Białka uczestniczące w transporcie jonów żelaza(II) w bakteriach gram-ujemnych
    Proteins involved in the ferrous ions transport in gram-negative bacteria
    Autorzy:
    Kierpiec, Karolina
    Stokowa-Sołtys, Kamila
    Powiązania:
    https://bibliotekanauki.pl/articles/1413209.pdf
    Data publikacji:
    2021
    Wydawca:
    Polskie Towarzystwo Chemiczne
    Tematy:
    transport jonów żelaza(II)
    bakterie gram-ujemne
    Feo
    ferrous iron transport
    Hmu
    hemin uptake protein
    ferrous ions transport
    gram-negative bacteria
    Opis:
    Continuous increase in the number of multidrug-resistant strains forces us to look for drugs with completely new mode of action. One of the bacterial property determining the pathogenicity of these microorganisms is their ability to obtain iron. Because in the living environment of these single-celled individuals, its concentration is much lower than this necessary for their growth. For this reason, bacteria created various type of iron aquisition systems, including the Feo system, which mechanism of Fe2+ ion uptake is not fully understood, and protein from the Hmu family belonging to ABC transporters. The Feo transport system is one of the most common systems that is exclusively responsible for importing Fe2+ ions. It consists of three proteins: FeoA, FeoB and FeoC. FeoB is a transmembrane protein that is believed to play a key role in the mechanism of Fe2+ ion uptake. The other two components are cytoplasmic proteins. Both, FeoA and FeoC, are cytoplasmic proteins resembling the construction of transcription regulators. ABC transporters play an equally important role in maintaining iron homeostasis. These include proteins from Hmu family. HmuUV complex catalyses the import of these ions in hem iron form. The structure of this complex consists of TMD dimer (HmuU) and NBD dimer (HmuV). The HmuU is considered to be a permease - just like the FeoB described earlier while HmuV is the ATP binding protein.
    Źródło:
    Wiadomości Chemiczne; 2021, 75, 3-4; 375-394
    0043-5104
    2300-0295
    Pojawia się w:
    Wiadomości Chemiczne
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Oddziaływanie elektronów z cząsteczkami o biologicznym znaczeniu
    Interaction of electrons with biologically relevant molecules
    Autorzy:
    Kopyra, J.
    Powiązania:
    https://bibliotekanauki.pl/articles/171628.pdf
    Data publikacji:
    2015
    Wydawca:
    Polskie Towarzystwo Chemiczne
    Tematy:
    dysocjacyjny wychwyt elektronów
    spektrometria mas
    jony ujemne
    cząsteczki o biologicznym znaczeniu
    dissociative electron attachment
    mass spectrometry
    negative ions
    biologically relevant molecules
    Opis:
    Recent years have witnessed an increase of the interest in the studies of the interaction of electrons with biologically relevant molecules. This has been mainly motivated by the seminal work, where it has been demonstrated that low energy electrons can induce single and double strand breaks in DNA in the energy range below the level of ionization. Since the damage profile as a function of electron energy showed pronounced resonances it was proposed that resonant electron capture could occur at particular molecular components of the DNA as the initial step towards strand breaks. From a series of experiments on electron attachment to DNA building blocks (nucleobases, the sugar moiety and the phosphate unit) became obvious that they effectively capture electrons leading to the formation of low energy resonances associated with the decomposition of the corresponding molecule. Recent dissociative electron attachment experiments on an entire gas phase nucleotide 2’-deoxycytidine-5´-monophosphate give also insight into the molecular mechanism involved, which comprises both direct electron attachment to the backbone and transfer of the excess electron from cytosine to the backbone resulting in single strand breaks. The results further allow an estimate of the relative contribution of these different mechanisms to single strand breaks.
    Źródło:
    Wiadomości Chemiczne; 2015, 69, 9-10; 893-907
    0043-5104
    2300-0295
    Pojawia się w:
    Wiadomości Chemiczne
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Wiązanie jonów na granicy faz oraz specyficzne efekty jonowe
    Ion binding to interfaces and specific ion effects
    Autorzy:
    Jakubowska, A.
    Powiązania:
    https://bibliotekanauki.pl/articles/172482.pdf
    Data publikacji:
    2012
    Wydawca:
    Polskie Towarzystwo Chemiczne
    Tematy:
    wiązanie jonów
    metody badawcze
    teorie i modele
    specyficzne efekty jonowe
    binding of ions
    research methods
    theories and models
    specific ion effects
    Opis:
    Many biological processes taking place across or at membrane surfaces depend on the interaction between interfaces and ions (derived from the background salt) [1]. Binding of ions to surfactant bilayers, nucleic acids, proteins, and biological membranes markedly affects their stability and properties [2–8]. There are different techniques to measure the ion binding to interfaces, including: nuclear magnetic resonance (NMR) spectroscopy [2, 18-20], the method based on measuring of electrophoretic mobility and the so-called zeta potential measurements [4, 21], the method based on measuring of a ratio of acid-to-base forms of the spectrophotometric indicator pyridine- 2-azo-p-dimethylaniline, PADA [12], and the chemical-trapping method [22]. The above-mentioned methods permit investigation of the binding of either cations or anions to interfaces. Many theories and models had been proposed to describe quantitatively the interactions and distribution of ions at a charged surface. The earliest one was proposed by Gouy and Chapman [23, 24]. However, the classical Gouy–Chapman theory was too simplified due to the neglect of the geometrical dimensions of the ions [27]. Other theories have been developed on the basis of the Poisson–Boltzmann theory and the Poisson–Boltzmann equation (equation 3). This equation has been modified by an introduction of different terms [25, 42]. Recently, Radke et al. proposed interesting models of the ion distribution near the interface: the ion binding model [28] (Fig. 1) and the ion image charge interaction model [51] (Fig. 3). Interaction and binding of ions with interfaces is related to the so-called specific ion effects arising at exchanging ions of the same valence. Franz Hofmeister, Professor of Pharmacology at the University of Prague was the first who studied these effects systematically [13, 14]. The specific ion effects play a significant role in a wide range of biological and physicochemical phenomena from the salt solubility, electrolyte activities, the surface tension of electrolyte solutions, values of pH and zeta potentials, the buffer acting, microemulsion microstructure, cloud points of polymers and surfactant solutions to the action of ions on ion-channels in biological membranes (ion transport across membranes), in enzyme activities, in bacterial growth, and in the interaction between membranes [15, 16]. The biological cell activity is also connected to Hofmeister effects. The ion specificity observed is, in fact, a combination of different subtle effects, such as ion size, hydration of ions, ion effect on interfacial water structure, electrostatic and dispersion interactions, thermal motion, and fluctuations [26, 29–31]. Because of a combination of those different effects, Hofmeister effects remain unexplained by the present theories of physical chemistry [16].
    Źródło:
    Wiadomości Chemiczne; 2012, 66, 3-4; 193-208
    0043-5104
    2300-0295
    Pojawia się w:
    Wiadomości Chemiczne
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Porfiryny zamknięte w żelu krzemionkowym
    Porphyrins closed in sol-gel matrix
    Autorzy:
    Wiglusz, R. J.
    Powiązania:
    https://bibliotekanauki.pl/articles/172034.pdf
    Data publikacji:
    2011
    Wydawca:
    Polskie Towarzystwo Chemiczne
    Tematy:
    porfiryny
    pochodne porfiryn
    jony lantanowców
    spektroskopia UV-VIS
    luminescencja
    zol-żel
    porphyrins
    porphyrin derivatives
    lanthanide(III) ions
    UV-Vis spectroscopy
    luminescence
    sol-gel
    Opis:
    The need for new, chemically and physically stable luminescent materials operating with UV excitations has stimulated research on luminescence properties of doped sol–gel material. In this work, it has been presented a technology of production of silica gels doped with organic molecules, lanthanide compounds and organic/inorganic composites. Optical properties of these materials as functions of temperature, concentration and excitation wavelength are presented. Dynamics of excited states has been discussed based on the decay times and emission efficiencies data. Mechanisms of ligand-to-metal energy transfer as well as other processes affecting emission efficiency are considered. Silica sol–gels doped with di-aminoacid derivatives of porphyrins: PP(Ser)2(Arg)2, PP(Ala)2(Arg)2, PP(Met)2(Arg)2, where Met, Arg and Ser denote methionine, serine and arginine aminoacids, respectively, and H2TTMePP {tetrakis[4-(trimethylammonio)phenyl]-21H,23H-porphine} have been obtained and spectroscopically studied. These materials can find applications as phosphors or sensors of UV irradiation.
    Źródło:
    Wiadomości Chemiczne; 2011, 65, 7-8; 675-703
    0043-5104
    2300-0295
    Pojawia się w:
    Wiadomości Chemiczne
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Rola metali w rozwoju choroby Alzheimera i Parkinsona
    The role of metals in development Alzheimer's and Parkinson's diseases
    Autorzy:
    Żygowska, Justyna
    Szymańska, Aneta
    Powiązania:
    https://bibliotekanauki.pl/articles/2057913.pdf
    Data publikacji:
    2022
    Wydawca:
    Polskie Towarzystwo Chemiczne
    Tematy:
    choroba neurodegeneracyjna
    jony metali
    β-amyloid
    białka amyloidogenne
    choroba Alzheimera
    choroba Parkinsona
    neurodegenerative diseases
    amyloidogenic proteins
    amyloid β
    metal ions
    Alzheimer's disease
    Parkinson disease
    Opis:
    Neurodegenerative diseases are the consequence of progressive brain degeneration caused by the death of nerve cells. Many factors that influence the neurodegeneration development are still not fully known. A lot of studies indicate the contribution of metal ions in this process. Copper, zinc, and iron are trace elements essential for proper functioning of the body. They are part of many enzymes participating in the transmission of the nerve signals, electrons transport, neurotransmitters and nucleic acids synthesis, and oxygen storage. Disorder of metals homeostasis leads to the development of severe diseases and nervous system degenerations. An excess of copper and iron ions causes a significant increase in cellular oxidative stress. Metals catalyze the reactions of free radicals formation that destroy proteins, lipids, and nucleic acids. High concentration of copper and iron ions were found in the deposits of amyloidogenic proteins. Amyloid β (Alzheimer disease) and α synuclein (Parkinson disease) have ions binding chain structures. The metal-protein interaction increases oligomerization speed in vitro. A lot of evidence suggests that the disorder of Cu, Zn and Fe homeostasis accelerates the progress of brain neurodegeneration. Human organism contains many metals, which are not needed for the proper functioning of the body, e.g. aluminum. Al binds to nucleic acids causing an increase in cellular oxidative stress and initiating proteins oligomerization. The presence of aluminum is also considered to be disadvantageous for the nervous system. The lack of medicines for neurodegenerative diseases forces us to search for new therapies. The development of degenerations could be slowed down by chelators of toxic metals, but first, these diseases must be better understood. Adverse effects of high concentration of metal ions on brain functioning are not fully known. This knowledge is necessary to find effective drugs.
    Źródło:
    Wiadomości Chemiczne; 2022, 76, 1-2; 1-25
    0043-5104
    2300-0295
    Pojawia się w:
    Wiadomości Chemiczne
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
      Wyświetlanie 1-12 z 12

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