The BGI researchers found that the Shiga-toxin-encoding genes, responsible for most of the pathogenicity of the disease, were likely encoded by a viral prophage that integrated in the bacterial chromosome
XerC and XerD normally serve to resolve circular bacterial chromosome
dimers generated by RecA mediated homologous recombination by adding a crossover at a specific 28 bp site dif on the chromosome (16).
Other technologies rely on either integrating the synthetic gene(s) into the bacterial chromosome
or using antibiotics and antibiotic resistance genes to amplify plasmids containing the new genes.
They added yeast DNA, including a centromere, and then inserted this doctored bacterial chromosome
into yeast, in which it replicated and was also susceptible to further engineering.
This enables the generation of multiple, site-specific knockouts in the same bacterial chromosome
A unique feature of phage P1 is that during lysogeny its genome is not incorporated into the bacterial chromosome
as is commonly observed during lysogeny bo other bacteriophage.
To test whether these 300 or so genes alone can sustain life, Venter and his colleagues have contemplated making an artificial bacterial chromosome
containing only those genes.
IS element transposition is known to be stimulated by the cell stress response and can lead to the "hopping" of IS elements into plasmid DNA and or into other regions of the bacterial chromosome