Is a Common Precursor of the Aromatic Amino Acid Family

Chorismate Is a Common Precursor of the Aromatic Amino Acid Family 

Aromatic amino acid biosynthesis proceeds via a long series of reactions, most of them concerned with the formation of the aromatic ring before branching into the specific routes to phenylalanine, tyrosine, and tryptophan. Chorismate, the common intermediate of the three aromatic amino acids, (see fig. 21.1) is derived in eight steps from erythrose-4-phosphate and phosphoenolpyruvate. We focus on the biosynthesis of tryptophan, which has been intensively studied by both geneticists and biochemists. 

Tryptophan Is Synthesized in Five Steps from Chorismate 

The biosynthesis of tryptophan from the branchpoint compound, chorismate in E. coli The first step involves the conversion of chorismate to the aromatic compound anthranilate. The anthranilate is transferred to a ribose phosphate chain. The product is cyclized to indoleglycerol phosphate by the removal of water and loss of the ring carboxyl by indoleglycerol phosphate synthase. Finally, in a 

Distribution of Tryptophan Biosynthetic Enzyme Activities on Different Proteins in Bacteria and Fungi 

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Amino Acid Pathways Absent in Mammals Offer Targets for Safe Herbicides Chorismate Is a Common Precursor of the Aromatic Amino Acid Family... 

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