The Regulation of Synthesis of Phenolics in Stationary Phase Cell Cultures ofAcer pseudoplatanusL.

Abstract

The addition of 2/ (w/v) sucrose to stationary phase suspension cultures of sycamore (Acer pesudoplatanus) in medium depleted of nitrogen and phosphorus leads to the accumulation of high levels of phenolics after a 5 d lag period. Urea and 2,4-D inhibit this accumulation of phenolics. Urea results in a stimulation in cell protein content coincident with phenolics in hibition, and leads to a substantial diversion of the common precursor phenylalanine from phenolics synthesis into protein synthesis. 2,4-Dichlorophenoxyacetic acid (2,4-D) does not lead to protein accumulation since the cultures are nitrogen-limited, but stimulates an increase in protein turnover coincident with phenolics inhibition. The role of protein synthesis in the regulation of phenolics metabolism through competition for common precursors is discussed.