FIG. 6.

Effects of supplementation with glucose and shikimate together on growth (A), substrate consumption (B), and the expression of the qsu genes (C). The C. glutamicum R wild-type strain was cultured in BT minimal medium supplemented with either 40 mM glucose (Glc), 40 mM shikimate (Shi), or both at 20 mM each. (A) The optical densities at 610 nm (OD₆₁₀) of the cell cultures in the presence of glucose (white rectangles), shikimate (white circles), and both glucose and shikimate (black triangles) were monitored. (B) The concentrations of glucose (black rectangles) and shikimate (white diamonds) in medium during growth in the presence of both glucose and shikimate were measured. (C) The levels of qsuA, qsuB, qsuC, qsuD, and ptsG mRNAs in the cells cultured for 2 h with glucose, shikimate, and both glucose and shikimate were determined by quantitative RT-PCR. The mRNA levels are presented relative to the value for the shikimate-grown cells, except for ptsG mRNA levels, which are presented relative to the value for the glucose-grown cells. All the values are the means of results from three independent experiments with standard errors.