Dictionary.com
definitions

tryptophanase

[trĭp′tə-fə-nās′, -nāz′, trĭp-tŏf′ə-]
n.
  1. An enzyme that catalyzes the cleavage of tryptophan to indole, pyruvic acid, and ammonia and that is commonly found in bacteria.
  2. tryptophan 2,3-dioxygenase
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.