Fig. 4.

KaiC-ET specifically elevates bioluminescence level for the class 2 promoter P_purF. Shown are representative traces for the strains ΔkaiC (filled black diamonds), ΔkaiC complemented with KaiC-WT (filled black squares), KaiC-ET (filled orange squares) or KaiC-SE (open green circles). Note that, in WT, the peak bioluminescence occurs at 24, 48, and 72 h, the KaiC knockout is at the lower end of the circadian range, and the knockout complemented with KaiC-ET runs high whereas the knockout complemented with KaiC-SE runs low. This behavior is opposite that observed with P_kaiBC (Fig. 3). Blue vertical line at 24 h highlights that bioluminescence from this class 2 promoter is at maximal levels at dawn.