Pathway to recycle nutrient sulfur in plants is elucidated

May 25, 2021

Defense chemicals, glucosinolates function as nutrient reservoirs as well

An international collaborative research group, including the RIKEN CSRS, the Max Planck Institute for Plant Breeding Research, and the Polish Academy of Sciences, found a pathway that recycles sulfur by degrading endogenous glucosinolates, sulfur-rich secondary metabolites, in Arabidopsis thaliana.

Plants are sessile and thus protect themselves from herbivorous insects and pathogenic organisms by synthesizing various compounds called secondary metabolites. Since the synthesis requires a vast amount of energy and materials, it is essential for plants to balance allocations of those resources for the synthesis of secondary metabolites and their own growth as a survival strategy.

The collaborative research group elucidated the pathway in A. thaliana through which glucosinolates synthesized as defensive chemicals are degraded to produce cysteine, a sulfur-containing amino acid which is a constituent of the body. While the metabolic route from cysteine to glucosinolates has already been clarified, the retrograde pathway from glucosinolates, which have been considered as end products, to cysteine has been revealed at a molecular level for the first time.

The findings of this study will contribute to improving plant traits toward sustainable food production and the development of high-performance crops.

Original article
Proceedings of the National Academy of Sciences of the United States of America doi:10.1073/pnas.2017890118
R. Sugiyama, R. Li, A. Kuwahara, R. Nakabayashi, N. Sotta, T. Mori, T. Ito, N. Ohkama-Ohtsu, T. Fujiwara, K. Saito, R. Thomas Nakano, P. Bednarek, M. Yokota Hirai,
"Retrograde sulfur flow from glucosinolates to cysteine in Arabidopsis thaliana".
Masami Hirai
Team Leader
Metabolic Systems Research Team