The viability

of cells increased levels of RNase HI is reduced. Wild type cells carrying a P araBAD rnhA expression plasmid (pECR15) show a growth defect that depends on Veliparib supplier the concentration of arabinose present in the growth medium. Even growth on glucose, which suppresses expression from the P araBAD promoter, leads to a mild growth defect, presumably due to a combination of the high plasmid copy number and the leakiness of the P araBAD promoter. Cells carrying a control plasmid (P araBAD eCFP, pAST110) show no growth restriction. (PDF 447 KB) References 1. Champoux JJ: DNA topoisomerases: structure, function, and mechanism. Annu Rev Biochem 2001, 70:369–413.PubMedCrossRef 2. Deweese JE, Osheroff MA, Osheroff N: DNA Topology and

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