Part:BBa_K3040500

pFadBA promoter with consensus sequence rrnD promoter is one of the bacteria rRNA promoter. Our team intended to replace the leaked fadBA promoter with this endogenous promoter in E. coli to get a lower baseline expression. Moreover, upstream promoter elements is reported to interact with α-subunit of carboxy-terminal domain of RNA polymerase core enzyme to enhance the transcriptional activity of native promoter. Thus, we modified the rrnD promoter with TP24, an UP element from library built in the literature which is able to get a higher expression level than commonly used promoter OXB 15 to 9-fold. In order to regulate the expression of this promoter with fatty-acid, we inserted the fadR binding site before the Pribnow box to see whether the site has the greater impact toward the activity of promoter.