Involved in cell division and chromosome segregation (PubMed:24097947, PubMed:29378890). May influence the activity of FtsZ (PubMed:24097947). Binds DNA, but does not seem to function as a transcription factor (PubMed:24097947). Constitutively expressed throughout the growth phase. Mutant grows slower and cells are longer compared to the wild-type strain. Mutation has a relatively mild effect on the sporulation. Mutant is sensitive to reduced FtsZ concentrations. Deletion of the gene in a zapA mutant background results in very filamentous cells that are blocked in proper Z-ring formation (PubMed:24097947). Mutant shows increased internucleoid distances (PubMed:29378890). Belongs to the WhiA family.