Role of RNase H enzymes in maintaining genome stability in Escherichia coli expressing a steric-gate mutant of pol VICE391

pol VICE391 (RumA'2B) is a low-fidelity polymerase that promotes considerably higher levels of spontaneous SOS-induced mutagenesis than the related E. coli pol V (UmuD'2C). The molecular basis for the enhanced mutagenesis was previously unknown. Using single molecule fluorescence microscopy to visualize pol V enzymes, we discovered that the elevated levels of mutagenesis are likely due, in part, to prolonged binding of RumB to genomic DNA...