Summary
The rnh gene of Escherichia coli encodes RNase H. rnh mutants display at least two phenotypes: (1) they require functional RecBCD enzyme for growth; thus rnh-339::cat recB270 (Ts) and rnh-339::cat recC271 (Ts) strains are temperature sensitive for growth; (2) rnh mutants permit replication that is independent of the chromosomal origin, presumably by failing to remove RNA-DNA hybrids from which extra-original replication can be primed. We report here that manifestation of these two phenotypes occurs at different levels of RNase H function; we have examined partially functional rnh mutants for their in vitro RNase H activity, their ability to rescue viability in recB or recC cells and their ability to permit growth of mutants incapable of using oriC [dnaA (Ts)].
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Communicated G.R. Smith
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Itaya, M., Crouch, R.J. Correlation of activity with phenotypes of Escherichia coli partial function mutants of rnh, the gene encoding RNase H. Molec. Gen. Genet. 227, 433–437 (1991). https://doi.org/10.1007/BF00273934
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DOI: https://doi.org/10.1007/BF00273934