ATPase that plays an important role in maintaining flagellar number in Pseudomonas aeruginosa (PubMed:10629180, PubMed:28065505). Exhibits anti-activator activity against FleQ, the global transcriptional regulator of flagellar genes (PubMed:22581773, PubMed:28065505). ATP-binding allows dimerization and subsequent antagonistic effect against FleQ. Forms homodimers (PubMed:28065505). Interacts with FleQ (PubMed:22581773). Deletion results in up-regulation of flagellar genes that code for structural and regulatory proteins, leading to the multi-flagellated phenotype, which shows motility defect. Belongs to the ParA family.