Figure 3. UgtP oligomerization is sensitive to the changes in UDP-glc availability.

(A) YFP-UgtP re-localized from punctate foci to the cytoplasm and medial/polar rings in response to increases in intracellular UDP-glc levels within 20 minutes of expression of the UDP-glc synthesizing protein GtaB. JC313 gtaB∷spc thrC∷P_spachy-gtaB-cmyc amyE∷P_xyl-yfp-ugtP cells were cultured in nutrient-rich LB at 30°C. For T = 0 and T = 20 time points, membrane probe TMA-DPH was used.

(B) YFP-UgtP re-localized from the cytoplasm and medial/polar rings to punctate foci in response to decreases in intracellular UDP-glc levels within 20 minutes of expression of the UDP-glc binding protein YwqF. JC330 thrC∷Pspachy-ywqF amyE∷P_xyl-yfp-ugtP cells were cultured in nutrient-rich LB at 30°C. For T = 0 and T = 20 time points, membrane probe TMA-DPH was used.

(C) Shifting PL2423 amyE∷P_xyl-yfp-ugtP cells between nutrient-rich and nutrient-poor medium led to the protein synthesis independent re-localization of YFP-UgtP. Top: YFP-UgtP re-localized from the cytokinetic ring to punctate foci within 30 minutes of a shift from nutrient-rich LB to nutrient-poor minimal sorbitol. Bottom: YFP-UgtP re-localized from punctate foci to the cytokinetic ring within 30 minutes of a shift from nutrient-poor minimal sorbitol to nutrient-rich LB. Both experiments were conducted in the presence of 200 μg ml⁻¹ chloramphenicol to inhibit new protein synthesis and cells were cultured at 30°C with a mass doubling time ~40 minutes.

Note that exposure times are identical in A–B. In C, exposure times were increased to compensate for the lack of new protein synthesis in the latter image. Bar = 3 μm.