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Updated: Feb 26, 2026

Chemical Modification of the Tryptophan Residue in a Recombinant Ca2+-ATPase N-domain for Studying Tryptophan-ANS FRET
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Chemical Modification of the Tryptophan Residue in a Recombinant Ca2+-ATPase N-domain for Studying Tryptophan-ANS FRET

Published on: October 9, 2021

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Substrate Binding Primes Human Tryptophan 2,3-Dioxygenase for Ligand Binding.

Karin Nienhaus1, Vincent Hahn1, Manuel Hüpfel1

  • 1Institute of Applied Physics, Karlsruhe Institute of Technology (KIT) , Wolfgang-Gaede-Straße 1, 76131 Karlsruhe, Germany.

The Journal of Physical Chemistry. B
|July 18, 2017
PubMed
Summary

Human tryptophan 2,3-dioxygenase (hTDO) exists in two conformations affecting ligand binding. Substrate binding favors the fast-binding conformation, enhancing catalytic efficiency by preventing unproductive heme oxidation.

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