title: Polynucleotides. XLIV. Synthesis and properties of poly (2-azaadenylic acid) and poly(2-azainosinic acid).
abstract: Chemically synthesized 2-azaadenosine 5'-diphosphate (n2ADP) and 2-azainosine 5'-diphosphate (n2IDP) were polymerized to yield poly(2-azaadenylic acid), poly(n2A), and poly(2-azainosinic acid), poly(n2I), using Escherichia coli polynucleotide phosphorylase. In neutral solution, poly(n2A) and poly(n2I) had hypochromicities of 32 and 5.5%, respectively. Poly(n2A) formed an ordered structure, which had a melting temperature (Rm) of 20 degrees C at 0.15 M salt concentration. Upon mixing with poly(U), poly(n2A) formed a 1 : 2 complex with Tm of 41 degrees C at 0.15 M salt concentration. Poly(n2A) and poly(n2I) formed three-stranded complexes with poly(I), and poly(A), respectively. Poly(n2A) . 2poly(I), poly(A) . 2poly(n2I), and poly(n2A) . 2poly(n2I) complexes had Tm values of 23, 48, and 31 degrees C at 0.15 M salt concentration, respectively. Poly(n2I) formed a double-stranded complex with poly(C), but its Tm was very low.
mesh_terms: D002942:Circular Dichroism; D004926:Escherichia coli / Q000201:enzymology; D009691:Nucleic Acid Denaturation; D011061:Poly A / Q000138:chemical synthesis; D011069:Poly I / Q000138:chemical synthesis; D011117:Polyribonucleotide Nucleotidyltransferase; D011131:Polyribonucleotides / Q000138:chemical synthesis; D013056:Spectrophotometry, Ultraviolet
chemical_list: D011131:Polyribonucleotides; D011061:Poly A; D011069:Poly I; C018129:poly(2-azainosinic acid); C018128:poly(2-azaadenylic acid); D011117:Polyribonucleotide Nucleotidyltransferase