Persistence of RNA attached to nascent short DNA pieces in Bacillus subtilis cells defective in DNA polymerase I

Abstract

When cells of a pol A ts strain of Bacillus subtilis in logarithmic growth phase are raised to the restrictive temperature, a large amount of newly synthesized short DNA pieces accumulates. Analysis with spleen exonuclease has indicated that RNA-linked nascent DNA pieces accumulate in the pol A ts cells about 4.5 times as much as in the pol A + cells. These observations suggest that B. subtilis DNA polymerase I is involved in the removal of the RNA attached to the nascent short DNA pieces as well as in the filling in of the gaps between these pieces.