Proposed catalytic mechanism of serine dehydratase. The serine substrate is red, the PLP cofactor is green, and the catalytic lysine is blue. The PLP phosphate group serves as a general base-general acid during the course of the reaction. Product aminoacrylate (frame 6, red) is ultimately hydrolyzed nonenzymatically to form pyruvate and ammonia. Reprinted with permission from: Yamada, T., Komoto, J., Takata, Y., Ogawa, H., Pitot, H. C., & Takusagawa, F. Crystal structure of serine dehydratase from rat liver. Biochemistry
42, 12854–12865 (2003). Copyright 2015 American Chemical Society.