Involved in the biosynthesis of the antibiotic phenazine, a nitrogen-containing heterocyclic molecule. PhzB1 (operon phzA1B1C1E1F1G1) has a role in the biosynthesis of the phenazine during planktonic growth. Antibiotic biosynthesis; phenazine biosynthesis. Homodimer. Under control of LasR (PubMed:11544214). In liquid cultures (aerobic), phz1 operon is induced by quinolone signal via 2-heptyl-3-hydroxy-4-quinolone (PQS) (PubMed:23129634). In biofilm (microaerobic), phz1 operon is not induced by PQS, because the biosynthesis of PQS by the monooxygenase PqsH requires molecular oxygen (PubMed:23129634). Belongs to the PhzA/PhzB family.