title: Studies on Auxin Protectors. V. On the Mechanism of IAA Protection by Protector-I of the Japanese Morning Glory.
abstract: The mechanism of auxin protection by auxin protector-I (Pr-I) of the Japanese morning glory was studied in vitro. Four lines of evidence indicate that Pr-I acts as a strong reductant which prevents the peroxidase-catalyzed oxidation of IAA: 1) The kinetics of the reaction are best explained on this basis. 2) The Pr-I-induced lag preceding auxin destruction by peroxidase is completely eliminated by a strong oxidant such as H(2)O(2) at a concentration which does not appreciably affect the reaction rate. 3) Strong organic reductants mimic the Pr-I-induced lag. And 4) when the reaction rate is altered by varying the concentrations of the reactants, or the temperature, the length of the Pr-I-induced lag varies inversely with the reaction rate.
authors.affiliation: Laboratory of Plant Morphogenesis, Manhattan College, Bronx, New York 10471.
authors.forename: T
authors.initials: T
authors.lastname: Stonier
authors.forename: Y
authors.initials: Y
authors.lastname: Yoneda
authors.forename: F
authors.initials: F
authors.lastname: Rodriguez-Tormes