Identification and development of a glucaric acid biosensor in Saccharomyces cerevisiae

Metabolic biosensors are increasingly used in metabolic engineering and synthetic biology.In this study,using Saccha-romyces cerevisiae as a model system,we developed a methodology to identify promoter elements that are responsive to glucaric acid.Through transcriptome analysis,it was found that multiple genes were upregulated when cells were exposed to high concentrations of glucaric acid.From the promoters of these candidate genes,the YCR012W promoter(PYCR012W)was observed to specifically respond to glucaric acid in a dose-dependent manner.To gain further insight into the binding site of glucaric acid-responsive activators,we truncated the promoter and revealed that the-564 to-464 bp regions of PYCR012W was essential for glucaric acid-responsive expression.To investigate the glucaric acid-responsive transcription factors,we predicted the transcription factor binding sites in the-564 to-464 bp region of PYCR012W and found that two transcription factors,Ash1p and Cbf1p,might be linked to glucaric acid responses.The strategies used in this study outline a method for the identification and development of metabolic biosensors.