Abstract: A genetic screen based on the blue-white beta-galactosidase complementation assay designed to detect G-->A mutations arising during RNA-dependent DNA synthesis was used to compare the fidelity of mutant human immunodeficiency virus type 1
reverse transcriptases (
RTs) with the mutations
M230L and
M230I with the wild-type enzyme, in the presence of biased deoxynucleoside triphosphate (dNTP) pools.
Abstract: The mutant
RTs with the
M230L and
M230I changes were found to be 20 to 70 times less faithful than the wild-type
RT in the presence of low [dCTP]/[dTTP] ratios but showed similar fidelity in assays carried out with equimolar concentrations of each nucleotide.