0000000000465513
AUTHOR
Julio Salguero
1-Naphthyl Acetate-Dependent Medium Acidification by Zea mays L. Coleoptile Segments
Zea mays L. cv INRA 5a coleoptile segments ecidify the incubation medium on the addition of 1-naphthyl acetate (1-NA). The buffering capacity of the bathing solution increases during 1-NA stimulated medium acidification. The solution bathing the 1-NA treated coleoptile segment was analyzed by high performance liquid chromatography. A considerable amount of acetic acid was detected in the bathing solution used to measure 1-NA-dependent medium acidification. For the first time, the data demonstrate directly the release of acetic acid from 1-NA. The extent of medium acidification was proportional to 1-NA concentration. Simultaneous measurement of medium acidification and acetate content upon a…
Relationship between Auxin-Dependent Proton Extrusion and Plasmalemma Redox System in Maize Coleoptile Segments
Abraded coleoptile segments reduce ferricyanide utilizing endogenous substrates. The kinetics of ferricyanide reduction shows an initial rapid rate followed by a slow rate of reduction. The duration of the initial phase is about 5 minutes. The slow phase is observed for more than 30 minutes. A Lineweaver-Burk plot of the slow phase was linear and revealed maximum velocity of the reaction of 42 nmols ferricyanide reduced/hour*coleoptile segment and an apparent Km (ferri) of 2.25mM.