(Modeling proteins) (Chymotrypsin Mechanism: Step 1, Step 2, Step 3, Step 4, Step 5, Step 6)

Transition state between Steps 4 and 6 of Chymotrypsin Mechanism

  (PDB file) (ARC file)

In this reaction, water hydrolyzes the ester between Trp252 and Ser195, and a proton migrates onto Thr253. In the transition state, a hydrogen of  H2O is moving to the oxygen of Ser195. The proton of  H2O has completed the move to the amine group of Thr353, the oxygen of H2O has completed the move to the carbonyl carbon of Trp252, and the Ser195 oxygen to Trp252 bond has been broken. This transition state is the same as that for Steps 3-6. Step 3 and Step 4 differ in the distance of Thr253 from Trp252. Toggle display all Toggle center picture Fit to screen Interesting parts: His57 Gly193 Asp194 Ser195 Trp252 Thr253 H2O Toggle spin Toggle stereo