Extended Data Figure 5: Identifying chromosomal rearrangement in ΔoriC1,2,3 ΔradA strain H1553.
From: Accelerated growth in the absence of DNA replication origins
a, Map of SfaAI restriction sites on the main chromosome of wild isolate DS2. The region around ISH18 HVO_0278 is shown with additional restriction sites and the probe. b, Map of SfaAI restriction sites on the main chromosome of laboratory strain H26. The region downstream of integrated pHV4 is shown with the same restriction sites as in Extended Data Fig. 5a, and two extra probes (ori-pHV4 and bgaH) that hybridize to pHV4. c, Map of SfaAI restriction sites on the main chromosome of ΔoriC1,2,3 ΔradA strain H1553. The region downstream of integrated pHV4 is shown as in Extended Data Fig. 5b. H1553 has undergone a chromosomal rearrangement involving part of pHV4 between ISH18 HVO_A0014 and ISH18 HVO_0278. These ISH18 elements are identical in sequence but in an inverted orientation (bold arrows); recombination between them results in inversion of the intervening sequence. d, Restriction fragment length polymorphisms in H26 and H1553. Genomic DNA from wild isolate DS2, laboratory strain H26, ΔoriC1,2,3 strain H1501 and ΔoriC1,2,3 ΔradA strain H1553 was digested with SfaAI and shown on a pulsed-field gel. Southern blots were probed with the ori-pHV4 origin, bgaH gene (located on pHV4 (ref. 21)) and sequences downstream (DS) of ISH18 element HVO_0278. e, Confirmation of restriction fragment length polymorphisms by ClaI, KpnI and NarI digests, probed with sequences downstream (DS) of ISH18 element HVO_0278; see also Extended Data Fig. 4.
