Editing Tryptophan synthase (section)

=== α subunit reaction ===
The α subunit catalyzes the formation of indole and G3P from a retro-aldol cleavage of IGP. The αGlu49 and αAsp60 are thought to be directly involved in the catalysis as shown.<ref name="Overview" /> The rate limiting step is the isomerization of IGP.<ref name="a Rate Limiting Step">{{cite journal |vauthors=Anderson KS, Miles EW, Johnson KA | author-link2=Edith Wilson Miles|title = Serine modulates substrate channeling in tryptophan synthase. A novel intersubunit triggering mechanism | journal = J Biol Chem | volume = 266 | issue = 13 | pages = 8020–33 |date=May 1991 | doi=10.1016/S0021-9258(18)92934-0| pmid = 1902468 | doi-access=free}}</ref> See image 2.