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Nucleotides reversible template polymerization

DNA-directed DNA polymerases [EC 2.7.7.7], also called DNA nucleotidyltransferases (DNA-directed), are enzymes that catalyze the DNA template-directed extension of the 3 -end of a nucleic acid strand one nucleotide at a time. Thus, n deoxynucleoside triphosphates produce n pyrophosphate (or, diphosphate) ions and DNA . This enzyme cannot initiate the synthesis of a polymeric chain de novo it requires a primer which may be DNA or RNA. RNA-directed DNA polymerases [EC 2.7.7.49], also referred to as reverse transcriptases, DNA nucleotidyltransferases (RNA-directed), and revertases, are enzymes that catalyze the RNA template-directed extension of the 3 -end of a nucleic acid strand one nucleotide at a time. Thus, n deoxynucleoside triphosphates produce n pyrophosphate (or, diphosphate) ions and DNA . As was the case above, this enzyme cannot initiate the synthesis of a polymeric chain de novo it requires a primer which may be DNA or RNA. [Pg.210]

Telomerase is a ribonucleoprotein complex that exists in eukaryotic cells for the apparently sole purpose of synthesizing telomeric DNA, which consists of tandemly repeated sequences that contain clusters of G-residues and forms the ends of chromosomes. Telomerase comprises two essential core components, a protein subunit that has reverse transcriptase (RT) activity and an RNA sequence (hTR) that contains clusters of C-residues and serves as the template substrate for the RT (6). The G-rich DNA and C-rich RNA anneal to form a partial duplex with DNA as the primer. RT-mediated polymerization of dGTP and other complementary triphosphate substrates produces a DNA terminus that has been extended by around six nucleotides. The new end can become a substrate for either another round of telomerase-mediated elongation or primase/polymerase-mediated lagging-strand synthesis. [Pg.1686]

Template-induced polymerization of nucleotides. The idea is to have one single-stranded polynucleotide (e.g. poly A) as guest in reverse micelles, as well as an excess of mononucleotide (e. g. U or of short oligomers thereof). The binding A=U should produce an array of U lined up to the poly A matrix, and the polymerization should then take place by chemical activation. The process, if successful, can lead to any series of block copolymers or random copolymers. [Pg.211]


See other pages where Nucleotides reversible template polymerization is mentioned: [Pg.656]    [Pg.407]    [Pg.376]    [Pg.1386]    [Pg.264]    [Pg.172]    [Pg.54]    [Pg.103]    [Pg.441]   
See also in sourсe #XX -- [ Pg.164 , Pg.165 , Pg.165 ]




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