Sulfate Uptake, Cysteine and GSH Contents Are Increased by 5-Aminolevulinic Acid in Arabidopsis thaliana

Abstract

A key precursor of porphyrin biosynthesis, 5-aminolevulinic acid (ALA), is used as a fertilizer to promote plant growth and crop yields. Carbon fixation and nitrogen assimilation are promoted by ALA in plants, but the effect on other metabolic pathway has not been elucidated. In this study, we analyzed the effect of ALA on sulfur assimilation. Treatment with 0.3 and 1 mmol(-1) ALA significantly increased the sulfate uptake and the transcript levels of key sulfur transport and assimilatory genes. The accumulation of cysteine and glutathione was increased in shoots but decreased in roots. These data demonstrated a new role of ALA that regulates positively transcript levels of some sulfur assimilatory genes, sulfate uptake and contents of cysteine and glutathione.