The Saccharopine Pathway is the main degradation pathway of Lysine in plants and animals. Defects in the ALDH7A1 gene causes PDE, a rare epilepsy disease. The project aims to produce mutated SDH domain of the AASS enzyme, the main enzyme responsible for the convertion of Saccharopine in AASA(Aminoadipate Semialdehyde). Being an important enzyme for the Lysine Catabolism, the mutated SDH domain can then be used to verifiy the important residues via enzyme kinectics.