The PES scanning for the interconversion reaction of chorismate into the prephenate in the gasphase was determined by the Gaussian09 . For geometry optimization and frequency calculations, we used the hybrid B3LYP/def2-SVP level of theory . The effects of EEFs were also studied using Gaussian09. A range of electric field strengths (Fy) was explored while allowing to be oriented along the y-axis i.e., the reaction axis, along which the bonds are being broken and formed. For the geometry optimization in the presence of EEF, we used internal coordinates to avoid the misalignment of the EEF during the variation of the geometry.