Allylthiourea is a metabolic inhibitor that selective inhibits ammonia oxidation.Target: OthersAllylthiourea selectively inhibits ammonia oxidation at concentrations 8-80 μM. Allylthiourea (1 μM)inhibits ammonia oxidation by 80%. Complete inhibition is observed at an Allylthiourea concentration of 86 μM [1]. The inhibition of Allylthiourea on ammonia oxidation probably acts through chelating the copper of the ammonia monooxygenase active site. Allylthiourea is able to produce soluble methane monooxygenase (sMMO) in the presence of copper. Addition of 25 μM Allylthiourea decreases intracellular copper by 48% in Methylosinus trichosporium OB3b, allowing sMMO production at Cu/biomass ratios normally not permitting sMMO synthesis, which achieves a plateau of 320 μmol naphthol formed per gram dry biomass per hour [2].

References:
[1]. Ginestet, P., et al., Estimation of nitrifying bacterial activities by measuring oxygen uptake in the presence of the metabolic inhibitors allylthiourea and azide. Appl Environ Microbiol, 1998. 64(6): p. 2266-8.
[2]. Yu, Y., J.A. Ramsay, and B.A. Ramsay, Use of allylthiourea to produce soluble methane monooxygenase in the presence of copper. Appl Microbiol Biotechnol, 2009. 82(2): p. 333-9.