3-Amino-1,2,4-triazole

3-Amino-1,2,4-triazole (3-AT) is a heterocyclicorganic compound that consists of 1,2,4-triazole with an amino group as a substituent.

3-AT is a competitive inhibitor of the product of the HIS3 gene, imidazoleglycerol-phosphate dehydratase.^[3][4] Imidazoleglycerol-phosphate dehydratase is an enzyme catalyzing the sixth step of histidine production.^[5]

3-AT is also a nonselective systemic triazoleherbicide used on nonfood croplands to control annual grasses and broadleaf and aquatic weeds. It is not used on foodcrops because of its carcinogenic properties. As an herbicide, it is known as aminotriazole, amitrole or amitrol.

Amitrol was included in a biocide ban proposed by the Swedish Chemicals Agency^[6] and approved by the European Parliament on January 13, 2009.^[7] Amitrol's mode of action is unknown, though it is classed as a resistance group Q herbicide.^[8]

By applying 3-AT to a yeast cell culture which is dependent upon a plasmid containing HIS3 to produce histidine (i.e. its own HIS3 analogue is not present or nonfunctional), an increased level of HIS3 expression is required in order for the yeast cell to survive. This has proved useful in various two-hybrid system, where a high-affinity binding between two proteins (i.e., higher expression of the HIS3 gene) will allow the yeast cell to survive in media containing higher concentrations of 3-AT. This selection process is performed using selective media, containing no histidine.

El 9 de noviembre de 1959, el secretario del Departamento de Salud, Educación y Bienestar de los Estados Unidos , Arthur S. Flemming , anunció que parte de la cosecha de arándanos de 1959 estaba contaminada con trazas del herbicida aminotriazol. ^{[ 9 ]} El mercado de arándanos se desplomó y los productores perdieron millones de dólares. ^{[ 10 ]} Sin embargo, Ocean Spray se recuperó expandiendo el mercado del jugo de arándano, que, aunque ampliamente disponible para la venta, hasta entonces no era popular. Esto aseguró que los productores de arándanos no tuvieran que depender principalmente de las ventas de Acción de Gracias y Navidad, como sucedió hasta el incidente de 1959.