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Biopolymers Jan 1972
Topics: Deoxyribonucleotides; Energy Transfer; Hydroxylation; Optical Rotatory Dispersion; Polynucleotides; Potentiometry; Ribose
PubMed: 5008185
DOI: 10.1002/bip.1972.360110104 -
Biochimica Et Biophysica Acta May 1966
Topics: Adenine Nucleotides; Chemical Phenomena; Chemistry, Physical; Nucleotidyltransferases; Polynucleotides; Spectrophotometry; Ultraviolet Rays
PubMed: 5961622
DOI: 10.1016/0005-2787(66)90184-5 -
Biochimica Et Biophysica Acta Mar 1966
Topics: Adenine Nucleotides; Alkylation; Guanine Nucleotides; Polynucleotides; Spectrophotometry; Ultraviolet Rays
PubMed: 5914315
DOI: No ID Found -
Journal of Biochemistry Sep 1971
Topics: Cells, Cultured; Ligases; Plants; Polynucleotides
PubMed: 5120674
DOI: 10.1093/oxfordjournals.jbchem.a129669 -
Proceedings of the National Academy of... Sep 1967
Topics: Animals; Chemical Phenomena; Chemistry; Culture Techniques; Interferons; Mice; Polynucleotides; Rabbits; Trypsin; Virus Diseases
PubMed: 5233831
DOI: 10.1073/pnas.58.3.1004 -
Biochimica Et Biophysica Acta Nov 1995Bovine pancreatic ribonuclease A is an enzyme that catalyses the depolymerization of RNA. This process involves the interaction of the enzyme with the polymeric... (Review)
Review
Bovine pancreatic ribonuclease A is an enzyme that catalyses the depolymerization of RNA. This process involves the interaction of the enzyme with the polymeric substrate in the active site and its correct alignment on the surface of the enzyme through multiple binding subsites that essentially recognize the negatively charged phosphate groups of the substrate. The enzyme shows a strong specificity for pyrimidine bases at the 3'-position of the phosphodiester bond that is cleaved and a preference for purine bases at the 5'-position and, probably, for guanine at the next position. On the other hand, the enzyme shows a clear preference for polynucleotide substrates over oligonucleotides. In this review the contributions to the catalytic mechanism of some amino-acid residues that are located at non catalytic binding subsites are analysed.
Topics: Animals; Binding Sites; Catalysis; Cattle; Kinetics; Models, Chemical; Molecular Structure; Oligonucleotides; Pancreas; Phosphates; Polynucleotides; RNA; Ribonuclease, Pancreatic
PubMed: 7492594
DOI: 10.1016/0167-4838(95)00138-k -
Journal of Virology Feb 1972An adeno-associated virus containing bromodeoxyuridine-substituted deoxyribonucleic acid has been fractionated by equilibrium centrifugation in CsCl into two classes of...
An adeno-associated virus containing bromodeoxyuridine-substituted deoxyribonucleic acid has been fractionated by equilibrium centrifugation in CsCl into two classes of virions which contain complementary polynucleotide chains.
Topics: Adenoviridae; Bromodeoxyuridine; Carcinoma; Cell Line; Centrifugation, Density Gradient; DNA, Single-Stranded; DNA, Viral; Helper Viruses; Humans; Methods; Mouth Neoplasms; Nucleic Acid Denaturation; Nucleic Acid Renaturation; Phosphorus Isotopes; Polynucleotides; Tritium
PubMed: 5014934
DOI: 10.1128/JVI.9.2.394-396.1972 -
The Journal of Biological Chemistry Dec 1994Construction of chimaeric DNA molecules in vitro relies traditionally on two enzymatic steps catalyzed by separate protein components. Site-specific restriction...
Construction of chimaeric DNA molecules in vitro relies traditionally on two enzymatic steps catalyzed by separate protein components. Site-specific restriction endonucleases are used to generate linear DNAs with defined termini that can then be joined covalently at their ends via the action of DNA ligase. A novel approach to the synthesis of recombinant DNAs exploits the ability of a single enzyme, vaccinia DNA topoisomerase, to both cleave and rejoin DNA strands with extreme specificity at each step. Placement of the CCCTT cleavage motif for vaccinia topoisomerase near the end of a duplex DNA permits efficient generation of a stable, highly recombinogenic protein-DNA adduct that can religate only to acceptor DNAs that contain complementary single-strand extensions. Linear DNAs containing CCCTT cleavage sites at both ends (bivalent substrates) can be activated by topoisomerase and inserted into a plasmid vector in a simple and rapid in vitro procedure that is especially well suited to the molecular cloning of polymerase chain reaction-amplified DNAs. Activation of polyvalent (e.g. branched) DNA substrates by topoisomerase offers a potentially powerful method for the synthesis of two- and three-dimensional polynucleotide networks.
Topics: Base Sequence; Cloning, Molecular; DNA Topoisomerases, Type I; DNA, Recombinant; Molecular Sequence Data; Polynucleotides; Vaccinia virus
PubMed: 7798275
DOI: No ID Found -
Macromolecules 1975A simplified single virtual bond scheme has been developed for the calculation of mean-square unperturbed dimensions in polynucleotide chains. As a consequence of the...
A simplified single virtual bond scheme has been developed for the calculation of mean-square unperturbed dimensions in polynucleotide chains. As a consequence of the structural rigidity of the sugar residues in the chain, it is possible to represent the six chemical bonds comprising the chain backbone repeating unit by a single virtual bond (connecting successive phosphorus atoms). The mutual orientation of a pair of adjoining virtual bonds is determined by the angles of rotation about the phosphodiester bonds adjoining intervening phosphorus atoms and is independent of the orientation of all other virtual bonds in the chain. Computed values of chain dimensions based on the single virtual bond scheme are comparable to those calculated previously using a two virtual bond model which permits rotational flexibility in the sugar moieties of the chain.
Topics: Binding Sites; Mathematics; Nucleic Acid Conformation; Polynucleotides
PubMed: 1152526
DOI: 10.1021/ma60045a006 -
Journal of Drug Targeting Jan 2015Polynucleotides are anionic macromolecules which are expected to transfer into the targeted cells through specific uptake mechanisms. So, we developed polynucleotides...
Polynucleotides are anionic macromolecules which are expected to transfer into the targeted cells through specific uptake mechanisms. So, we developed polynucleotides coating complexes of plasmid DNA (pDNA) and polyethylenimine (PEI) for a secure and efficient gene delivery system and evaluated their usefulness. Polyadenylic acid (polyA), polyuridylic acid (polyU), polycytidylic acid (polyC), and polyguanylic acid (polyG) were examined as the coating materials. pDNA/PEI/polyA, pDNA/PEI/polyU, and pDNA/PEI/polyC complexes formed nanoparticles with a negative surface charge although pDNA/PEI/polyG was aggregated. The pDNA/PEI/polyC complex showed high transgene efficiency in B16-F10 cells although there was little efficiency in pDNA/PEI/polyA and pDNA/PEI/polyU complexes. An inhibition study strongly indicated the specific uptake mechanism of pDNA/PEI/polyC complex. Polynucleotide coating complexes had lower cytotoxicity than pDNA/PEI complex. The pDNA/PEI/polyC complex showed high gene expression selectively in the spleen after intravenous injection into mice. The pDNA/PEI/polyC complex showed no agglutination with erythrocytes and no acute toxicity although these were observed in pDNA/PEI complex. Thus, we developed polynucleotide coating complexes as novel vectors for clinical gene therapy, and the pDNA/PEI/polyC complex as a useful candidate for a gene delivery system.
Topics: Animals; Cell Line, Tumor; DNA; Erythrocytes; Gene Expression; Gene Transfer Techniques; Genetic Therapy; Genetic Vectors; Mice; Nanoparticles; Particle Size; Plasmids; Polyethyleneimine; Polynucleotides; Spleen; Static Electricity; Surface Properties
PubMed: 25148610
DOI: 10.3109/1061186X.2014.950665