Steric gate residues of Y-family DNA polymerases DinB and pol kappa are crucial for dNTP-induced conformational change

- DinB and pol κ probed by hydrogen/deuterium exchange (HDX)-mass spectrometry.
- DinB and pol κ had reduced HDX in ternary complexes with dNTP relative to rNTP.
- Mutation of steric gate resulted in ternary complexes with sugar-independent HDX.
- The steric gate residue is crucial for dNTP-induced conformational change.
- Discrimination against rNTP occurs in a closed polymerase conformation.