title: A Novel Class of Herbicides (Specific Inhibitors of Imidazoleglycerol Phosphate Dehydratase).
abstract: A new mode of herbicidal action was established by finding specific inhibitors of imidazoleglycerol phosphate dehydratase, an enzyme of histidine (His) biosynthesis. Three triazole phosphonates inhibited the reaction of the enzyme with Ki values of 40 [plus or minus] 6.5, 10 [plus or minus] 1.6, and 8.5 [plus or minus] 1.4 nM, respectively, and were highly cytotoxic to cultured plant cells. This effect was completely reversed by the addition of His, proving that the cytotoxicity was primarily caused by the inhibition of His biosynthesis. These inhibitors showed wide-spectrum, postemergent herbicidal activity at application rates ranging from 0.05 to 2 kg/ha.
authors.affiliation: International Research Laboratories, Ciba-Geigy Japan Ltd., P.O. Box 1, Takarazuka 665, Japan (I.M., S.-i.M., S.T., Y.K., G.I., J.-i.M., M.H., T.N., S.-i.K., A.S., K.H., D.O.).
authors.forename: I.
authors.initials: I
authors.lastname: Mori
authors.forename: R.
authors.initials: R
authors.lastname: Fonne-Pfister
authors.forename: Si.
authors.initials: S
authors.lastname: Matsunaga
authors.forename: S.
authors.initials: S
authors.lastname: Tada
authors.forename: Y.
authors.initials: Y
authors.lastname: Kimura
authors.forename: G.
authors.initials: G
authors.lastname: Iwasaki
authors.forename: Ji.
authors.initials: J
authors.lastname: Mano
authors.forename: M.
authors.initials: M
authors.lastname: Hatano
authors.forename: T.
authors.initials: T
authors.lastname: Nakano
authors.forename: Si.
authors.initials: S
authors.lastname: Koizumi
authors.forename: A.
authors.initials: A
authors.lastname: Scheidegger
authors.forename: K.
authors.initials: K
authors.lastname: Hayakawa
authors.forename: D.
authors.initials: D
authors.lastname: Ohta