The molecular mechanism of inhibition of alpha-type DNA polymerases by N2-(butylphenyl)dGTP and 2-(butylanilino)dATP: variation in susceptibility to polymerization.
Calf thymus DNA polymerase alpha (pol alpha) and bacteriophage T4 DNA polymerase (pol T4) were exploited as model enzymes to investigate the molecular mechanism of inhibitory action of N2-(p-n-butylphenyl)dGTP (BuPdGTP) and 2-(p-n-butyl-anilino)dATP (BuAdATP) on the BuPdNTP-susceptible alpha polymerase family. Kinetic analysis of inhibition of pol alpha with mixtures of complementary and noncomplementary template:primers indicated that both nucleotides induced the formation of a polymerase: inhibitor:primer-template complex. Primer extension experiments using the guanine form as the model analog indicated that pol alpha cannot utilize these nucleotides to extend primer termini. In contrast, pol T4 polymerized BuPdGTP, indicating that resistance to polymerization is not a common feature of the inhibitor mechanism among the broad membership of the alpha polymerase family.
Khan
N N
NN
Department of Pharmacology, University of Massachusetts Medical School, Worcester 01655.
Wright
G E
GE
Brown
N C
NC
D000255:Adenosine Triphosphate / Q000031:analogs & derivatives* / Q000494:pharmacology; D000818:Animals; D001483:Base Sequence; D002417:Cattle; D004259:DNA-Directed DNA Polymerase / Q000235:genetics; D003848:Deoxyguanine Nucleotides / Q000494:pharmacology*; D007700:Kinetics; D008969:Molecular Sequence Data; D019384:Nucleic Acid Synthesis Inhibitors; D011108:Polymers; D013604:T-Phages / Q000201:enzymology; D013698:Templates, Genetic; D013950:Thymus Gland / Q000201:enzymology
D003848:Deoxyguanine Nucleotides; D019384:Nucleic Acid Synthesis Inhibitors; D011108:Polymers; C040364:N(2)-(4-n-butylphenyl)-2'-deoxyguanosine 5'-triphosphate; D000255:Adenosine Triphosphate; C047394:4-n-butylanilino dATP; D004259:DNA-Directed DNA Polymerase