Reaction: histidine => urocanate + NH4+

- in pathway: Histidine catabolism
Cytosolic histidine ammonia lyase (HAL) catalyzes the reaction of histidine to form urocanate and NH4+ (Kawai et al. 2005).
Reaction - small molecule participants:
NH4+ [cytosol]
UCA [cytosol]
L-His [cytosol]
Reactome.org reaction link: R-HSA-70899

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Reaction input - small molecules:
L-histidinium(1+)
ChEBI:32513
Reaction output - small molecules:
ammonium
ChEBI:28938
trans-urocanic acid
ChEBI:30817
Reactome.org link: R-HSA-70899