Rec BC, sbc B independent, (AT) ⁿ - mediated deletion of sequences flanking a Xenopus laevis β globin gene on propagation in E. coli Open Access

Plasmids containing sequences 3' of the adult βl globin gene of Xenopus laevis are unstable on propagation in a range of E.coli host strains. Up to 300 bp of Xenopus DNA are lost by rec A independent recombination between (AT) ¹⁷ and (AT) ³⁷ sequences. Additionally, smaller deletions occurring in or around the (AT) ³⁷ sequence are observed.Deletion of these potential cruciform structures occurs in the absence of exonuclease I, exonuclease V and exonuclease VIII as the same pattern of deletion events is observed in recA recBC sbcB and recBC sbcA recE strains.