Live cell studies of bacterial DNA replication, recombination, and degradation

It seems that the evolution of life on this planet repeatedly acknowledges the value of
the genetic information, by providing an abundant variety of elegant mechanisms for the repair of damage occurring to DNA. The need for such mechanisms tells us that the state of cellular DNA is under constant threat of disintegration and decay. This may be obvious now, but was previously neglected and it took almost two decades after the discovery of the double-helix structure of DNA to realize that DNA is subject to a range of distinct forms of damage. Double-stranded breaks (DSBs) are a particularly dangerous damage occurring when both of the DNA strands are broken at the same position along the DNA. In order to recover the integrity of the genome, the broken strands must undergo an elaborate process to find a repair template elsewhere in the cell where the same genetic code is imprinted. In this thesis we focus on aspects of the repair of such lesions and we approach this problem from multiple angles to obtain insights into the processing of breaks and the relation between the homology search and the spatial organization of bacterial genome.