RNA-dependent DNA polymerase

RNA-dependent DNA polymerase (RT) is an enzyme that synthesizes DNA from an RNA
template in retroviruses. The Klenow fragment (KF), part of E. coli DNA polymerase I (Pol I), is
similar to RT molecule and exhibits RT activity. The HIV-1 RT inhibitor, AZT, has been reported to
be bactericidal against some species of bacteria. This finding indicates that AZT targets bacterial
polymerase which possesses RT activity. In this study, we analyzed the RT activities of E. coli,
Shigella sonnei I, Vibrio cholerae non-O1, Pseudomonas aeruginosa and Staphylococcus
aureus. Except in Staphylococcus aureus, AZT-TP inhibited bacterial RT activities. Expect in P.
aeruginosa, these results corresponded to the effect of AZT against these bacterial species. We
further determined the similarity of bacterial DNA polymerases by examination using inhibitory
antibodies obtained from a rabbit immunized with E. coli KF (anti-KF). Anti-KF inhibited the RT
activities of E. coli and S. sonnei I. Our findings indicate that the bacterial DNA polymerases which
possess RT activities may be targets of antibiotic therapy.