FIG. 2.

Dynamics of StkP substrate phosphorylation during growth. (A) Activity of StkP during growth in complex medium. Proteins phosphorylated on Thr were detected with anti-pThr antibody (anti-pThr) in cell lysates of wild-type strain Sp1 prepared from logarithmic-phase (OD₄₀₀, 0.2 to 1.5) and stationary-phase (OD₄₀₀, 1.6) cultures. (B) Activity of StkP during growth arrest. Cultures of strain Sp1 were grown in glucose-containing CAT medium until the OD₄₀₀ was 0.4 and then centrifuged, resuspended in CAT medium with glucose (Glu+) or without glucose (Glu−), and cultivated for 1 h. Phosphorylated proteins were detected with anti-pThr antibody. The total amount of StkP protein in both experiments was evaluated with anti-StkP serum (anti-StkP). The arrow indicates the position of StkP.