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Wpływ dodatku kwasu deoksyrybonukleinowego (DNA) na właściwości mechaniczne żeli żelatynowych

Głazowska Joanna, Tylingo Robert, Bartoszek Agnieszka

Przemysł Chemiczny

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2019

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T. 98, nr 8

1224--1229

PL

Kwasy nukleinowe cieszą się coraz większym zainteresowaniem pod względem zastosowania ich w przemyśle farmaceutycznym, kosmetycznym oraz żywnościowym. Określono wpływ dodatku długo- i krótkołańcuchowych kwasów nukleinowych na właściwości mechaniczne żeli żelatynowych. Badania wykazały występowanie specyficznych interakcji pomiędzy żelatyną a kwasami nukleinowymi oraz pozwoliły na ocenę wpływu tych oddziaływań na twardość, kohezyjność, gumowatość oraz lepkość żeli.

EN

Two pork gelatin solns. were prepd. in deionized H2O (6.66 and 10% by mass) at 65°C and then gelled at 10°C for 24 h. The well-defined portions of the gelatin were added to solns. of two types of nucleic acids (short- and long-chain, gDNA and fDNA, resp.) dissoloved in a buffer (Tris-HCl and EDTA, pH 7.5) and mixed with deionized H2O to obtain concns. in the range of 0.001–0.1% by mass. The hardness, cohesiveness, elasticity, gumminess and viscosity at 40°C of obtained gelatin gels were detd. The mech. parameters of gelatin gels were deteriorated in the presence of gDNA but an improvement of these parameters was obsd. for the gel cong. 10% gelatin and 0.1% fDNA.

2

Biochromatografia oligonukleotydów

Pietrzak L., Studzińska S., Buszewski B.

Analityka : nauka i praktyka

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2014

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nr 1

20--25

PL

Oligonukleotydy to krótkie, jednoniciowe fragmenty kwasów nukleinowych. Ich podstawowym budulcem są nukleotydy składające się z trzech elementów: reszty fosforanowej, zasady azotowej oraz pentozy. Najważniejszą fizyczną właściwością oligukleotydów jest ich hydrofobowo-hydrofilowy charakter.

3

A study on interaction between ethyl violet and nucleic acids and its analytical application

Liu B., Lu L., Huang Y., Yu Z.

Chemia Analityczna

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2009

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Vol. 54, No. 4

733-742

EN

An interaction mechanism between ethyl violet and nucleic acids and their quantitative determination have been reported. Reaction mechanism indicated that binding of EV to yRNA proceeds mainly via electrostatic interactions and hydrogen bond formation with the phosphate groups. Resonance light scattering (RLS) of ethyl violet was greatly enhanced by nucleic acids. Based on this, ethyl violet was used as the RT,S probe for determination of nucleic acids.

PL

Opisano mechanizm oddziaływania między fioletem etylowym (EV) i kwasami nukleinowymi oraz ich ilościowe oznaczanie. Mechanizm rekacji wskazuje że wiązanie EV z yRNA zachodzi głównie przez oddziaływania elektrostatyczne i powstawanie wiązań wodorowych z grupami fosforowymi. Rezonansowe rozproszenie światła (RLS) fioletu etylowego było znacznie wzmacniane w obecności kwasów nukleinowych. Na tej podstawie fiolet etylowy zastosowano jako wskaźnik RLS do oznaczania kwasów nukleinowych.

4

Systemy znakowania fluorescencyjnego w real-timie PCR. Cz. 1

Skommer J.

LAB Laboratoria, Aparatura, Badania

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2003

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R. 8, nr 3

6-8

PL

Technika PCR zrewolucjonizowała technologię detekcji i pracy z kwasami nukleinowymi. Tradycyjny PCR (czy RT-PCR; RT - ang. reverse transcription, reakcja odwrotnej transkrypcji) z detekcją kwasów nukleinowych na etapie końcowym (w fazie plateau) rozwinął się w technologię umożliwiającą przeprowadzenie takiej detekcji w trakcie trwania procesu (faza logarytmiczna) - real-time PCR (kinetyczny PCR).

5

Study on the interactions between nitidine chloride and nucleic acids and its applications

Qin W., Wang S., Liu Z., Gong G.

Chemia Analityczna

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2003

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Vol. 48, No. 2

189-201

EN

A fluorescence method for the quantitative determination of nucleic acids has been proposed, which utilizes the enhancement of the fluorescence intensity of the nitidine chloride (NC) in the presence nucleic acids in aqueous solutions. Strong hypochromism, red shifts and isosbestic points (260 nm) in the absorption spectra were observed when NC binds to the calf thymus DNA (ctDNA), which suggested the intercalation mechanism of NC binding to DNA bases. Iodide quenching studies showed that the magnitude of AT of the free NC was higher than that of the bound NC. Thermal denaturation experiments revealed that the increase of the NC fluorescence in the presence of single strand (dsDNA) was smaller than in the presence of double strand (dsDNA). NC binding mode was also investigated with Scatchard plots. The results have also proved the intercalation of NC among DNA bases. The maximum fluorescence was observed within the pH range: 6.8-9.2, at the maximum excitation and emission wavelengths of 395 and 510 nm, respectively. Under optimum conditions, the measured fluorescence intensity in the presence of nucleic acids was proportional to the nucleic acids concentration over the range of 0.10-4.0 ug ml(-1) for ctDNA, 0.20-4.0 ug ml(-1) for thermally denatured ctDNA and 0.25-4.0 ug mL(-1) for yeast RNA. The corresponding detection limits were 39 ng ml/1 for ctDNA, 71 ng mL(-1) for thermally denatured ctDNA and 83 ng mL(-1) for for yRNA. The method has been successfully applied to the determination of DNA in real honey samples.

PL

Zaproponowano metodę ilościowego oznaczania kwasów nukleinowych opartą na wykorzystaniu wzmocnienia fluorescencji chlorku nitydyny (NC) w roztworach wodnych pod wpływem kwasów nukleinowych. W trakcie wiązania się NC z DNA grasicy cielęcej (ctDNA) obserwowano w widmach absorpcyjnych efekty hipochromowy i batochromowy oraz punkt izozbestyczny (260 nm) co sugerowało mechanizm wtrącenia NC do zasad DNA. Badania wygaszania fluorescencji pod wpływem jodków wykazały, że wartość AT wolnego NC była wyższa niż analogiczna wartość związanego NC. Badania nad denaturacją termiczną wykazały, że DNA w postaci pojedynczej nici (ssDNA) słabiej wzmacnia fluorescencję NC niż DNA o podwójnej nici (dsDNA). Przedyskutowano także badania sposobu wiązaniaNC za pomocą wykresów Scatcharda. Wszystkie te badania także wskazują, że NC zostaje wtrącony w stos zasad DNA. Maksymalna fluorescencja występowała w zakresie pH 6.8-9.2 odpowiednio: 395 nm i 510 nm. W optymalnych warunkach różnicowa wartość natężenia fluorescencji w nieobecności i obecności kwasów nukleinowych była proporcjonalna do stężenia tych kwasów w zakresie 0.10-4.0 ug ml(-1) dla ctDNA, 0.2-4.0 dla termicznie zdenaturowanego ctDNA oraz 0.25-4.0 ug mL(-1) dla RNA z drożdży. Granice detekcji wynosiły odpowiednio: 39 ng mL(-1) dla ctDNA, 71 ng ml(-1) dla termicznie zdenaturowanego ctDNA i 83 ng mL(-1) dla yRNA. Metodę zastosowano z powodzeniem do oznaczania DNA w rzeczywistych próbkach miodu.

6

Dichroizm kołowy kwasów nukleinowych. Cz.2. Polimery

Boczkowska M.

Wiadomości Chemiczne

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2002

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[Z] 56, 3-4

203-221

EN

The review presents the theoretical basis for interpretations of CD spectra of polynucleotides. A simplified version of quantum theory of circular dichroism of a polynucleotide by Tinoco and Johnson is presented in details. It is generally assumed that the optical activity of these polymers is dominated by interactions between dipoles of in-plane transitions occuring at neighbouring bases. The interaction of dipoles coming from different bases strictly depends on geometrical arrangement of bases within the helix. As a result information about geometry of the helix can be inferred from the CD spectra. The circular dichroism caused by the disturbance of the electronic system of a base by the presence of a sugar ring is usually omitted in calculations. Such a theoretical approach allows to understand differences between CD spectra of random DNA and RNA. The distance of a base pair from helix axis appeared to be the main factor responsible for these differences]. The approach fails in a case of polymers of non-random sequences, for example containing a repetitive motif of two bases. It is exemplified for the d(CG)n oligomers forming left-handed double helix called Z-DNA, where none of the theoretical calculations is able to predict the inversion of a CD spectrum characteristic for the Z form .

7

Dichroizm kołowy kwasow nukleinowych. Cz.1. Monomery

Boczkowska Małgorzata

Wiadomości Chemiczne

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2002

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[Z] 56, 1-2

39--56

EN

The review presents the theoretical basis for the origin of optical activity of nucleic acids. The optical properties of nucleic bases are discussed in terms of theoretical calculations by Hug and Tinoco. Although nucleic bases are themselves optically inactive, the in-plane (pŽp*) as well as out-of-plane (nŽp*) transition dipoles induced in their rings are responsible for optical activity of nucleosides, nucleotides and polynucleotides. In a case of nucleosides and nucleotides, which are called "monomers", the optical activity originates from the disturbance of the electronic system of a base caused by the presence of a sugar ring. The main factor influencing the character of CD spectra is the torsion angle about the glycosyl bond. The experimental spectra of monomers are dominated by in-plane transitions. In a case of cytidine and guanosine (Rys. 3) the lowering of pH reveals the presence of the out-of-plane transition.

8

Selekcja kwasów nukleinowych in vitro

Nawrot B.

Wiadomości Chemiczne

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2000

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[Z] 54, 7-8

615-636

EN

In vitro selection of nucleic acids (Systematic Evolution of Ligands by Exponential Enrichment - SELEX) is the selection technique which, from the library of randomised or degenerated RNA or DNA molecules, allows the isolation of nucleic acids with expected biochemical properties. Repeated cycles of selection and amplification have been used to isolate sequences of nucleic acids (aptamers) that bind with high affinity specific molecular targets - proteins or low molecular weight ligands. This method allows also to isolate a number of nucleic acids with catalytic activity and thus to generate new ribozymes and deoxyribozymes. SELEX is an useful tool of molecular biology and bioorganic chemistry for developing new therapeutic agents, as well for the insight in function of RNA in molecular evolution and RNA World hypothesis.

9

Jony metali jako czynnik ingerujący w oddziaływaniach poliamin z fragmentami kwasów nukleinowych

Łomozik L., Gąsowska A.

Wiadomości Chemiczne

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2000

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[Z] 54, 1-2

87--103

EN

Structurally simple aliphatic polyamines: putrescine (Put), spermidine (Spd) and spermine (Spm) occur in the cells of living organisms (human, animals, plants and bacteria) in relatively high concentrations. These compounds participate in many living processes [1-4 and references therein]. High basicity of polyamines implies that in the physiological conditions they appear in the protonated form and thus can interact with the negative fragments of other biomolecules. According to the polyelectrolytic theory of Manning, structural changes of particular molecules in interactions with the other components of the system depend mainly on the charge of the reagents, however, this approach does not explain a high specificity of certain reactions. It has been recently suggested that apart from the charge, also the polycation structure seems to play an important role. Computer analysis of the potentiometric titration data allowed a determination of the stability constants of molecular complexes formed by polyamines and fragments of the nucleic acids. Analysis of the titration and the spectral data indicates that at least two active centers are needed to obtain a relatively stable adduct. The thesis saying that the main sites of interactions are the protonated amine groups from PA and the negative or high electron density fragments of nucleosides or nucleotides (ion-dipole or ion-ion interactions) has been confirmed by the pH ranges of the molecular complexes occurrence. In nucleosides and nucleotides the main sites of metallation are the donor endocyclic N(3) atoms from the pyrimidine ring and N(1) or N(7) atoms from the purine ring. Phosphate groups of nucleotides are also effective centers of reaction. Polyamines change the character of the coordination dichotomy (mixture of isomers with the N(1) or N(7) coordination) observed in the metal-nucleoside (or nucleotide) systems. In general, with increasing length of the polyamine, the tendency to formation of heteroligand mixed complexes decreases and, interestingly, this tendency is exactly the opposite to that of formation of molecular complexes Nuc/PA. Already small changes in the polyamine length significantly affect their complex formation properties and reactions with metal ions or molecules in living cells. This explains the differences in the properties of biogenic amines and their biologically inactive homologues. In the ternary systems Cu/Nuc/Spm and Cu/NMP/Spm some interesting differences were observed in the coordination mode of the complexes. In the complex Cu(Nuc)(Spm) the metal ion was found to coordinate four nitrogen atoms from the polyamine in the equatorial plane and the N(3) or N(7) atom at the axial position (coordination structure of the square pyramid). In the system with the nucleotide, Cu(II) binds the phosphate group, while the polyamine is involved in non-covalent interaction with the donor nitrogen atoms from the purine or pyrimidine base and forms an adduct with intermolecular non-covalent complex-ligand interactions. In the systems with nucleosides, copper ions inhibit the interactions of adenosine or cytidine with polyamines. On the other hand, spermine involved in the non-covalent interaction with a nucleotide base blocks the potential metallation sites of AMP or CMP, changing essentially the character of coordination. Considering the role of the complexation processes in the above model systems, it should be added that formation of PA complexes with metal ions and fragments of nucleic acids is a factor ensuring homeostasis of polyamines in living cells. Reduction of the effect of diamine oxidase on the amines involved in the complexation processes increases their lifetime in living organisms.

10

Conformational changes of 5SrRNA from Lupin seeds and tRNAPhe in the presence of Cu2+ and Pb2+ cations by DSC method

Zielenkiewicz A.

Bulletin of the Polish Academy of Sciences. Chemistry

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2000

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Vol. 48, No. 2

181-188

EN

The results of calorimetric studies of 5SrRNA isolated from Lupinus luteus and of tRNA (Phe) both in the absence and in the presence of different concentrations of cations Cu(2+), Pb(2+) are reported. The temperature and the enthalpy of melting have been determined. Using the deconvolution method the elementary transitions have been distinguished and discussed.