Expression of the sialidase and selected hyaluronidase genes in the wild-type, mutant and complemented strains.

RNA was isolated from cells grown in TPYG broth for 4 h, which corresponds to exponential growth phase. The relative expression of the nanI, nanJ, nagJ and nagL (A) and nagK (B) genes was determined by QRT-PCR. Expression levels are relative to the expression of the housekeeping gene rpoA and are the average of three independent biological replicates (± SEM). The asterisk (*) denotes a statistically significant difference (p≤0.05) as calculated using the student’s t-test.