Tryptophan Operon PO L trpE trpD trpC trpB trpA Leader Met-Lys-Ala-Ile-Phe-Val-Leu-Lys-Gly-Trp-Trp-Arg-Thr-Ser Threonine Met-Lys-Arg-lle-Ser-Thr-Thr-lle-Thr-Thr-Thr-lle-Thr- lle-Thr-Thr-Gly-Asn-Gly-Ala-Gly Histidine Met-Thr-Arg-Val-GIn-Phe-Lys-His-His-His-His His-His-His-Pro-Asp Phenylalanine Met-Lys-His-lle-Pro-Phe-Phe-Phe-Ala-Phe-Phe- Phe-Thr-Phe-Pro Figure 8.20Figure 8.20 Tryptophan Operon