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       <h3>Tetrathionate Sensor TtrSR</h3>
-      <p>To identify the lesion site, we need a molecule that specifically characterizes IBD. Current research suggests that thiosulfate and tetrathionate can serve as indicators of intestinal inflammation (Levitt et al., 1999), and the levels of thiosulfate or tetrathionate are directly proportional to the severity of intestinal inflammation. A previous study constructed a tetrathionate sensor in E. coli (Kristina N-M Daeffler, 2017). This system is the TtrSR two-component system (TCS) from the marine bacterium Shewanella halifaxensis HAW-EB4. The TCS includes TtrS, a membrane-bound sensor histidine kinase (SK), which can phosphorylate the cytoplasmic response regulator (RR) TtrR in the presence of tetrathionate. Phosphorylated TtrR activates the expression of downstream genes through the ttrB promoter (PttrB).</p>
+      <p>To identify the lesion site, we need a molecule that specifically characterizes IBD. Current research suggests that thiosulfate and tetrathionate can serve as indicators of intestinal inflammation<sup>1</sup>, and the levels of thiosulfate or tetrathionate are directly proportional to the severity of intestinal inflammation. A previous study constructed a tetrathionate sensor in E. coli<sup>2</sup>. This system is the TtrSR two-component system (TCS) from the marine bacterium Shewanella halifaxensis HAW-EB4. The TCS includes TtrS, a membrane-bound sensor histidine kinase (SK), which can phosphorylate the cytoplasmic response regulator (RR) TtrR in the presence of tetrathionate. Phosphorylated TtrR activates the expression of downstream genes through the ttrB promoter (PttrB).</p>
       <p>To verify the effectiveness of the tetrathionate sensor TtrSR, we designed the corresponding plasmids. We planed to express EGFP downstream of ttrB and validate the effect of TtrSR by testing the fluorescence intensity of the cells. We used Ura-HIS nutrient-deficient medium to select yeast that had been successfully transformed. Then, we tested the effectiveness of the TtrSR system using confocal microscopy. For more details, please refer to protocol.</p>
       <p>Aim:</p>
       <p>To confirm the effectiveness of TtrRS in Saccharomyces cerevisiae</p>