title: Action of DNA polymerase I of Escherichia coli with DNA-RNA hybrids as templates.
abstract: Experiments indicating the ability of the ribo strand of a DNA-RNA template to guide polydeoxynucleotide synthesis by highly purified DNA polymerase I of E. coli (EC 2.7.7.7) are presented. With poly(rA).poly(dT) as template, poly(dT) is formed with a high efficiency, but almost no poly(dA). The specific activity of the enzyme, when tested with this template under suitable conditions, is eight times greater than that found for the poly(dA-dT) template. Single-stranded DNA fractions, with no template activity for DNA polymerase, are converted to efficient templates after their transcription by RNA polymerase. A concerted polymerization reaction, in which the action of DNA polymerase is dependent on that of RNA polymerase, can also be demonstrated with synthetic polydeoxynucleotides and single-stranded fractions of denatured DNA as templates.
mesh_terms: D000227:Adenine Nucleotides / Q000096:biosynthesis; D001410:Bacillus megaterium / Q000032:analysis; D004254:DNA Nucleotidyltransferases / Q000494:pharmacology*; D004269:DNA, Bacterial / Q000302:isolation & purification / Q000378:metabolism*; D003854:Deoxyribonucleotides / Q000096:biosynthesis; D004926:Escherichia coli / Q000187:drug effects / Q000201:enzymology*; D005815:Genetic Code; D006863:Hydrogen-Ion Concentration; D008274:Magnesium / Q000494:pharmacology; D008345:Manganese / Q000494:pharmacology; D009693:Nucleic Acid Hybridization; D011119:Polynucleotides / Q000096:biosynthesis*; D011189:Potassium Chloride / Q000494:pharmacology; D012316:RNA Nucleotidyltransferases / Q000494:pharmacology; D012329:RNA, Bacterial / Q000378:metabolism*; D013698:Templates, Genetic; D013942:Thymine Nucleotides / Q000096:biosynthesis
chemical_list: D000227:Adenine Nucleotides; D004269:DNA, Bacterial; D003854:Deoxyribonucleotides; D011119:Polynucleotides; D012329:RNA, Bacterial; D013942:Thymine Nucleotides; D008345:Manganese; D011189:Potassium Chloride; D004254:DNA Nucleotidyltransferases; D012316:RNA Nucleotidyltransferases; D008274:Magnesium