Polydeoxyribonucleotides

RN 83712-50-1 MF unspecified MW unspecified CN defibrotide polydeoxyribonucleotides from bovine lung... 

DNA (phosphodiester) hydrolysis has also been examined with [Co(cyclen)(OH2)(OH)]2+ as the active species.1239,1246 Significant rate enhancement of linear1247 and supercoiled1248 double-stranded polydeoxyribonucleotide hydrolysis is observed by immobilizing the Co complex on a polystyrene support. Wider exploration of reactions with DNA follow. 

DNA ligase (NAD+) [EC 6.5.1.2] (also referred to as polydeoxyribonucleotide synthase (NAD+), polynucleotide ligase (NAD+), DNA repair enzyme, and DNA join-ase) catalyzes the reaction of NAD+ with (deoxyribo-nucleotide) and (deoxyribonucleotide) to produce AMP, nicotinamide nucleotide, and (deoxyribonucleo-tide)( +m). This forms a phosphodiester at the site of a single-strand break in duplex DNA. RNA can also act as substrate to some extent. 

DNA is a polydeoxyribonucleotide that contains many monodeoxy-ribonucleotides covalently linked by 3 ->5 -phosphodiester bonds. With the exception of a few viruses that contain single-stranded DNA, DNA exists as a double-stranded molecule, in which the two strands wind around each other, forming a double helix. In eukaryotic cells, DNA is found associated with various types of proteins (known collectively as nucleoprotein) present in the nucleus, whereas in prokaryotes, the protein-DNA complex is present in the nucleoid. 

Bovine spleen phosphodiesterase hydrolyzes both polyribo- and polydeoxyribonucleotides... 

Nucleotides are the building blocks of nucleic acids their structures and biochemistry were discussed in chapter 23. When a 5 -phosphomononucleotide is joined by a phosphodiester bond to the 3 -OH group of another mononucleotide, a dinucleotide is formed. The 3 -5 -linked phosphodiester intemucleotide structure of nucleic acids was firmly established by Lord Alexander Todd in 1951. Repetition of this linkage leads to the formation of polydeoxyribonucleotides in DNA or polyribonucleotides in RNA. The structure of a short polydeoxyribonucleotide is shown in figure 25.3. The polymeric structure consists of a sugar phosphate diester backbone with bases attached as distinctive side chains to the sugars. 

Figure I. Schematic of a polydeoxyribonucleotide chain backbone showing the internal rotations (, ,

DNA. Deoxyribonucleic acid. A polydeoxyribonucleotide in which the sugar is deoxyribose the main repository of genetic information in all cells and most viruses, or "Deoxyribonucleic acid". The nucleic acid which carries the genetic code of an organism. It is the primary component of chromosomes. 

Defibrotide is a polydeoxyribonucleotide extracted from mammahan organ. Its antithrombotic activity is partly ascribed to enhancement of eicosanoid metabohsm, in particular increased release of prostacyclin, with ensuing... 

Bovine spleen phosphodiesterase hydrolyzes both polyribo- and polydeoxyribonucleotides Figure 5-43 Some hydrolytic cleavage reactions of polynucleotides. Reactions of both RNA and DNA are included. 

The templates which determine the base sequence of the product are either polydeoxyribonucleotides or polyribonucleotides, the initiator is either an oligodeoxyribonucleotide or an oligoribonucleotide, and the substrates are deoxyribonucleoside triphosphates. A proposed distinction between enzymes which utilized only polydeoxyribonucleotide templates from those which used only polyribonucleotide templates, and the introduction of the term reverse transcriptase for the latter are probably not justified on chemical grounds since DNA polymerases and reverse transcriptases can, with varying efficiencies, copy either template (28— 30). 

Italy defibrotide antithrombotic Noravid Prociclide Polydeoxyribonucleotides from mammalian organs with MW in the 15-30 kDa range Thrombosis... 

Poly [d(A-T)] containing a few [a-32p, uracil-3H]dUMP residues has been prepared using [a-32p, uracil- HldUTP as a substrate for Klenow fragment, and then treated successively with uracil N-glycosylase and T4 UV endonuclease V to afford polydeoxyribonucleotide chains with deoxyribose 5-[32p] phosphate residues at the... 

Defibrotide. Fraction P deft bri no tide Noravid Procielide, Sodium salt of polydeoxyribonucleotide extract from animal organs, mol wt 45.000-50,000 dal tons Prepn A. Butti et al. Ger, p t- 2,154 278 eidem. U.S. pat. 3 899,-481 (1972. 1975 both io Crinos). Antithrombotic activity R. Niada et al. Thromb, Res. 23, 233 (1981). Pharmacokinetics and profibrinolytic activity in rabbits R. Pescador et al, ibid. 30 1 (1983), Clinical trial as antithrombotic S. Coccheri et al. Int. J. Clin. Pharm. Res. 2, 227 (1982). Clinical evaluation in thrombotic microangiopathy V, Bono-... 

Karimi-Busheri, F. Weinfeld, M. Purification and substrate specificity of polydeoxyribonucleotide kinases isolated from calf thymus and rat liver. J. Cell. Biochem., 64, 258-272 (1997)... 

Fanta, M. Zhang, H. Bernstein, N. Glover, M. Karimi-Busheri, R Weinfeld, M. Production, characterization, and epitope mapping of monoclonal antibodies against human polydeoxyribonucleotide kinase. Hybridoma, 20, 237-242 (2001)... 

The term cytoplasmic DNA applies to DNA species found outside a nucleus either by morphological methods or biochemically, after homogenization and differential centrifugation. In the latter case the cytoplasmic DNA may be contaminated with degraded nuclear DNA. Except for comparatively short polydeoxyribonucleotide components attached to cytochrome b, and the DNA components (I-DNA) described by Bell and co-workers which occur in the cytoplasm of embryonic cells (cf. Section, II,C) extranuclear DNA is mainly localized within the mitochondria and chloroplasts of eukaryotic cells. Since mitochondrial DNA (mt DNA) is the only form of cytoplasmic DNA which is well characterized at the moment we shall concentrate on this. 

Single-strand break a break in a double-stranded DNA molecule which involves only one of the two strands, so that the molecule remains together. One S.s.b. is required to initiate unwinding of the double helix during replication. S.s.b. are caused by endonucleases, physical conditions or chemicals. Such breaks are repaired by the polydeoxyribonucleotide synthetases 6.5.1.1 and 6.5.1.2). 

Recently, evidence has emerged that in some DNAs with unusually regular base sequences, the sugar-phosphate backbone may adopt a very different conformation from that of the regular right-handed helix of R-DNA. This has been most clearly demonstrated with polydeoxyribonucleotides with a simple alternating sequence of two bases. Poly(dA-dT), in which deoxyadenosine alternates with deoxythymidine in each strand so that duplex formation is possible by the usual complementary base... 

Pfyffer GE, Pfyffer BU, Towers GHN 1982 Monoaddition of dictamnine to synthetic double-stranded polydeoxyribonucleotides in UVA and the effect of photomodified DNA on template activity. Photochem Photobiol 35 793-797... 

Table 2 (section 3.2.2.1) contains melting temperatures of polydeoxyribonucleotide hetero mplexes (including base-modified complexes), both double and triple stranded. 

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