The current interests of our laboratory center on the examination of proteins that generate closed hairpin ends in linear chromosomes and plasmids in DNA sequence specific manners.  Bacterial chromosomes and plasmids are usually circular, but in some cases, such as those in the causative agents of Lyme disease and relapsing fever in human, crown gall diseases in plant, and in a number of bacterial phages and viruses, they are linear with covalently closed hairpin ends.  The mechanisms with which the new form of chromosome conformation is formed and maintained are investigated using both biochemical, structural and genetics means.