FIG. 3.

malR transcript levels are elevated during growth of GAS in a maltotriose-medium and human saliva. Strain MGAS5005 was grown to the mid-exponential phase and late-exponential phase in THY, a maltotriose-medium, and human saliva. TaqMan real-time QRT-PCR was performed using primers and probes listed in Table 2. The transcript levels of target genes were normalized to those of proS, a gene that is expressed constitutively throughout the GAS cell cycle and whose transcript levels are similar when the organism is grown in THY and when the organism is grown in saliva (35, 43). The transcript levels are the means ± standard deviations of quadruplicate measurements obtained on two separate occasions.