Cell division and chromosome segregation in Staphylococcus aureus

Dissertação para a obtenção do grau de doutor em Biologia pelo Instituto de Tecnologia Química e Biológica. Universidade Nova de Lisboa

Bacterial cell division by binary fission involves several essential steps. Initially, the mother cell duplicates in size and replicates its DNA, in preparation for division. As the new sister chromosomes are synthesized, they are progressively segregated to the future daughter cells and once the division site is cleared of the majority of chromosomal DNA, the division septum starts assembling. The complete septum then constricts and, ultimately, the mother cell splits into two identical daughters. The generation of equal, viable progeny is strictly dependent on the regulation and coordination of these processes, both in space and in time. It is particularly important that the division septum is properly positioned at midcell and that chromosome segregation and cell division are synchronized, to prevent fragmentation of the genome by septum closure over the nucleoid.