Fig 7. Structural mutations within ICC alter phosphodiesterase activity.

(A) Paired NTHI isolates were obtained from middle ear effusion (MEE) or nasopharynx (NP) and the icc gene was sequenced as described in the Materials and Methods. Single nucleotide polymorphisms were observed that resulted in 5 amino acid changes (indicated in bold red and gray highlight). (B) Phosphodiesterase activity (PDE) of cytoplasmic extracts was assessed using the PDELight HTS cAMP phosphodiesterase kit and activity reported as relative light units (RLU). Three biological replicates were assayed in technical triplicate and statistical significance was determined using a two–tailed Student’s t test.