Recombination within Wolbachia ori sequences. Recombination results of the Wolbachia ori based on MaxChi (P < 0.001). (A) pattern of distribution of recombination breakpoints along the nucleotide alignment of 38 strains belonging to supergroup A and B. The cumulative number of recombination events per site is given. The alignment includes the beginning of locus COG1253 (WD1027, 1–168 bp), the intergenic non-coding region (INT, 169–586 bp), and the beginning of locus hemE (WD1028, 587–673 bp). Most of the breakpoints fall at the two edges of the intergenic region. Location of binding sites in the intergenic region is also shown. CtrA_1: 225-239 bp; CtrA_2: 489-503 bp (complementary strand); CtrA_3: 251-265 bp; CtrA_4: 228-242 (complementary strand); DnaA_1: 406-414 bp; DnaA_2: 461-469 bp; DnaA_3: 246-254 bp (complementary strand); IHF_1: 430-442 bp. Arrow indicates a major breakpoint. (B) Two examples of recombination among strains within supergroup B and between supergroup A and B. Only polymorphic sites are shown. For each example, putative recombination breakpoints are predicted based on the difference of shared polymophisms among the three strains and are indicated with an arrow (corresponding position in the nucleotide alignment is given). The wAenc_B Wolbachia ori sequence (belonging to supergroup B) is indicated as recombinant between the corresponding ori sequences of wMel_A (A-supergroup) and wMa_B (B-supergroup) strains. A similar recombination event, but among supergroup B strains, is observed in wCalt_B, which appears to be recombinant between wOsca_B and wVul_B.
Ioannidis et al. BMC Genomics 2007 8:182 doi:10.1186/1471-2164-8-182