title: Comparison of initiating abilities of primers of different length in polymerization reactions catalyzed by DNA polymerases from thermoacidophilic archaebacteria.
abstract: Optimal conditions for polymerization reaction catalyzed on poly(dA) and poly(dT) templates by DNA polymerases from thermoacidophilic archaebacteria--DNA polymerase A from Sulfolobus acidocaldarius and DNA polymerase B from Thermoplasma acidophilum--have been established. Values of Km and Vmax (60 degrees C) for a set of primers d(pA)n and d(pT)n have been estimated. Minimal primers for both enzymes are dNMP. Lengthening of primers by each mononucleotide increases their affinity about 2.16-fold. Linear dependence of log Km and of log vmax on the number of mononucleotide links in primers (n) has breaking point at n = 10. The value of Vmax is about 20% of that for decanucleotide. The affinity of the primer d(pA)9p(rib*) with a deoxyribosylurea residue at the 3'-end does not differ essentially from that of d(pA)9. Substitution of the 3'-terminal nucleotide of a complementary primer for a noncomplementary nucleotide, e.g., substitution of 3'-terminal A for C in d(pA)10 in the reaction catalyzed on poly(dT), decreases the affinity of a primer by one order of magnitude.
authors.affiliation: Institute of Molecular Biology and Biological Physics, Georgian SSR Academy of Sciences, Tbilisi, U.S.S.R.
authors.forename: I S
authors.initials: IS
authors.lastname: Bukhrashvili
authors.forename: D Z
authors.initials: DZ
authors.lastname: Chinchaladze
authors.forename: O I
authors.initials: OI
authors.lastname: Lavrik
authors.forename: A S
authors.initials: AS
authors.lastname: Levina
authors.forename: G A
authors.initials: GA
authors.lastname: Nevinsky
authors.forename: D A
authors.initials: DA
authors.lastname: Prangishvili
mesh_terms: D001105:Archaea / Q000201:enzymology*; D001419:Bacteria / Q000201:enzymology*; D004259:DNA-Directed DNA Polymerase / Q000378:metabolism*; D007700:Kinetics; D011061:Poly A; D011071:Poly T; D011067:Poly dA-dT; D013329:Structure-Activity Relationship; D013698:Templates, Genetic
chemical_list: D011061:Poly A; D011071:Poly T; C015465:poly(dA); D011067:Poly dA-dT; D004259:DNA-Directed DNA Polymerase