FIG 5.
Growth phenotype and raffinose operon gene expression in rafR exchange mutants. (A) S. pneumoniae strains 4559, 947, 4559947rafR, and 9474559rafR were grown in CDM+Glc or CDM+Raf, and OD600 was monitored for 12 h. Data are mean OD600 ± SD from triplicate assays. (B) The indicated strains were grown in CDM+Glc to an OD600 of 0.2, washed and resuspended in CDM+Raf, and then incubated at 37°C for a further 30 min. RNA was then extracted, and levels of aga, rafG, and rafK mRNA were analyzed by qRT-PCR. Data are the means ± SD from three independent experiments. *, P < 0.05, ***, P < 0.001, and ****, P < 0.0001, by unpaired t test.