Fig. 2: Optimization of constitutive mScarlet(I3) reporters.
a Schematic of constitutive reporter constructs with the indicated promoters driving expression of mScarlet (mSc) or mScarletI3 (mScI3, * = mScI3 (G228R)). LP encodes a leader peptide that functions to increase mSc(I3) levels. b Fluorescence microscopy of fixed cells expressing mScarlet or mScarletI3. The mScI3 signal was reduced in images marked with “ADJUSTED” because the PslpA::mScI3 reporter strain is 3–28-fold brighter than the other mSc(I3) reporter strains. Scale bar is 5 µm. Images are representative of three biological replicates. c Superplots of single-cell fluorescence intensity quantified using SuperSegger64 for the strains shown in (b). The outlined colored dots represent the median fluorescence measured for a given biological replicate. The horizontal black line indicates the mean fluorescence value determined for three biological replicates (unmarked WT n = 547; Pcwp2::LP-mSc n = 391; Pcwp2::LP-mScI3 n = 760; Pcwp2::LP-mScI3* n = 743; PgluD::mScI3 n = 443; PslpA::LP-mSc n = 498; PslpA::mScI3 n = 376). d Growth of the constitutive mSc(I3) reporter strains in BHIS broth based on optical density. A single biological replicate representative of three biological replicates is shown.
