The division during bacterial sporulation is symmetrically located in Sporosarcina ureae

Immunofluorescence microscopy was used to visualize the FtsZ band that marks the site of septation in Sporosarcina ureae . Image analysis indicated that the vegetative division was symmetrically located with respect to the ends of the cells. Fusions of lacZ to the sporulation loci, spoIIA and cotE , of Bacillus subtilis were introduced into S . ureae by mobilization of plasmids containing the fusions from Escherichia coli . The fusions showed similar patterns of sporulation-associated expression in S . ureae to those observed in B . subtilis . Formation of β-galactosidase encoded by the spoIIA–lacZ fusion made it possible to identify early sporulating cells by immunofluorescence microscopy. Analysis of the position of FtsZ bands in cells expressing spoIIA–lacZ indicated that the location of sporulation division was symmetrical with respect to the ends of the cells, in sharp contrast to the asymmetrical location of septation in sporulating Bacilli . It is inferred that asymmetry of location of the sporulation division is not essential for the compartmentalization of gene expression that follows the division.