Defining steric, electronic and conformational requirements of carrier-mediated uptake of abscisic acid in barley suspension culture cells

Autor: K. Brock Chatson, Suzanne R. Abrams, Michel R. Perras, Patricia A. Rose, Eric W. Pass, John Balsevich
Rok vydání: 1997
Předmět:
Zdroj: Phytochemistry. 46:215-222
ISSN: 0031-9422
DOI: 10.1016/s0031-9422(97)00299-9
Popis: The structural and conformational requirements of a carrier responsible for the saturable component of the uptake of the plant hormone (+)-abscisic acid in barley suspension culture cells have been probed through the use of a defined series of optically pure ABA analogues. Two analogues showed a tenfold increase over (+)-ABA in inhibiting the uptake of radiolabelled (+)-ABA. Results from different studies (molecular modelling, low temperature NMR spectroscopy and assays with sterically rigid analogues) have shown the likely conformation of ABA in the binding site of the carrier is that with the sidechain in an equatorial-like orientation. Structure/activity studies show that the C-1 carboxylic acid is essential for binding, the C-4 carbonyl is moderately important while the C-1′ hydroxyl group is not important for binding to the carrier.
Databáze: OpenAIRE