Step 1: The Regulator gene codes for an inactive repressor protein.
Step 2: If the corepressor tryptophan is present, it binds to to the inactive repressor protein.
Step 3: The binding of the corepressor causes inactive repressor protein to change shape and become activated.
Step 4: The activated repressor protein then binds to the Operator region of the trp operon.

Illustration of Function of A Repressible Operon in the Presence of a Corepressor (The Tryptophan Operon).jpg by Gary E. Kaiser, Ph.D.
Professor of Microbiology, The Community College of Baltimore County, Catonsville Campus
This work is licensed under a Creative Commons Attribution 4.0 International License.
Based on a work at https://cwoer.ccbcmd.edu/science/microbiology/index_gos.html.

Last updated: August, 2018
Please send comments and inquiries to Dr. Gary Kaiser