Discrimination of glucose metabolism (A) and homoserine lactone quorum sensing (B) based on differences in transcript ranks. Open symbols are glucose-absent or quorum sensing negative comparators in panels A and B, respectively. Filled symbols are glucose-present and quorum sensing positive comparators in panels A and B, respectively. Stars indicate drip-flow biofilm samples. The genes appearing in these graphs are annotated as: PA5564, gidB, glucose inhibited division protein B; PA3187, probable ATP-binding component of ABC transporter; PA2634, aceA, isocitrate lyase; PA3186, glucose/carbohydrate outer membrane porin OprB precursor; PA0485, conserved hypothetical protein; PA3724, lasB, elastase; PA3281, hypothetical protein; rhlA, rhamnosyltransferase chain A.