Since our project aims to demonstrate a regulatable levodopa yielding E coli., we design two system. One is composed of HpaBC after T7 promoter, and the other one express split T7RP. To achieve regulation, we apply photoswitches, Vvd, pMag-nMag, and pMagFast2-nMagHigh1 to receive the light and activate T7RP. Despite HpaBC is from BL21 genome, others are artificially synthesized. All the basic parts can be found in the final composite parts.