Selectivity of DNA polymerases toward α and β nucleotide substrates of d and l series

AbstractThe substrate properties of four carbocyclic d and l nucleoside 5′-triphosphate analogs toward HIV and AMV reverse transcriptases and terminal deoxynucleotidyl transferase were evaluated. The compounds of the d-β and l-β series were found to be terminating substrates for these enzymes, while the derivatives of the d-α and l-α series were recognized only by terminal deoxynucleotidyl transferase, suggesting that for the template-independent enzyme the mutual orientation of the two fragments is of no significance. A hypothesis for binding of nucleotides to the DNA polymerase active center was proposed