Recognition and use of the unusual X-DNA as a primer-template by Klenow DNA polymerase enzyme.
Based on CD spectra, 2-amino-2'-deoxyadenosine-containing synthetic alternating DNA, poly(amino2dA-dt) undergoes a conformational transition from a B-form to a non-Z zig-zag form of DNA, called X, even under conditions where enzymes can work. Kinetic parameters of the E. coli Klenow DNA polymerase enzyme-catalyzed copying of both the B- and X-forms of poly(amino2dA-dT) have been determined. Binding affinity of X-DNA to the enzyme proved to be even higher than that of the B-DNA; primer-chain extension of X-poly(amino2dA-dT) was however hindered as compared to its B-form. This differential utilization of X-DNA versus B-DNA by a DNA polymerase is an in vitro enzymatic evidence of an unusual DNA conformation.
Sági
J
J
Central Research Institute for Chemistry, Hungarian Academy of Sciences, Budapest.
Vorlícková
M
M
Kypr
J
J
Otvös
L
L
D002942:Circular Dichroism; D004247:DNA; D004256:DNA Polymerase I / Q000378:metabolism*; D004261:DNA Replication; D004926:Escherichia coli / Q000201:enzymology; D007700:Kinetics; D009690:Nucleic Acid Conformation; D011067:Poly dA-dT; D011089:Polydeoxyribonucleotides; D013698:Templates, Genetic
D011089:Polydeoxyribonucleotides; C054693:poly(amino(2)dA-dT); D011067:Poly dA-dT; D004247:DNA; D004256:DNA Polymerase I