Function
Chorismate synthase (CS) or 5-enolpyruvylshikimate-3-phosphate phopholyase is the seventh enzyme in the shikimate pathway which catalyzes the transition of phosphenol pyruvate to chorismate in prokaryotic bacteria and plants. Chorismate is a precursor for the synthesis of aromatic amino acids in the bacteria[1]. Cs also plays a role in the biosynthesis of nucleotides. CS catalyzes the conversion of 5-enolpyruvylshikimate-3-phosphate (EPSP) to chorismate. The activity of CS requires the presence of FMN.
Relevance
CS inhibitors which inhibit the shikimate pathway, serve as antimicrobial agents[2].
Structural highlights
The 3D structure of CS complex with its cofactor FMN and its substrate EPSP shows the EPSP binding site as very hydrophobic containing numerous Arg. Lys and His residues. The FMN cofactor has numerous interactions with CS and its phosphate moiety is located in the dimer interface and interacts with residues of the other monomer as well[3].
