From sulfur to homoglutathione: thiol metabolism in soybean.
Sulfur is an essential plant nutrient and is metabolized into the sulfur-containing amino acids (cysteine and methionine) and into molecules that protect plants against oxidative and environmental stresses. Although studies of thiol metabolism in the model plant Arabidopsis thaliana (thale cress) have expanded our understanding of these dynamic processes, our knowledge of how sulfur is assimilated and metabolized in crop plants, such as soybean (Glycine max), remains limited in comparison. Soybean is a major crop used worldwide for food and animal feed. Although soybeans are protein-rich, they do not contain high levels of the sulfur-containing amino acids, cysteine and methionine. Ultimately, unraveling the fundamental steps and regulation of thiol metabolism in soybean is important for optimizing crop yield and quality. Here we review the pathways from sulfur uptake to glutathione and homoglutathione synthesis in soybean, the potential biotechnology benefits of understanding and modifying these pathways, and how information from the soybean genome may guide the next steps in exploring this biochemical system.
Yi
Hankuil
H
Department of Biology, Washington University, St. Louis, MO 63130, USA.
Ravilious
Geoffrey E
GE
Galant
Ashley
A
Krishnan
Hari B
HB
Jez
Joseph M
JM
D000596:Amino Acids / Q000096:biosynthesis / Q000378:metabolism; D000603:Amino Acids, Sulfur / Q000096:biosynthesis / Q000378:metabolism*; D003545:Cysteine / Q000096:biosynthesis; D018506:Gene Expression Regulation, Plant; D005978:Glutathione / Q000031:analogs & derivatives / Q000096:biosynthesis; D053858:Metabolic Networks and Pathways; D008715:Methionine / Q000096:biosynthesis; D012639:Seeds; D013025:Glycine max / Q000235:genetics / Q000378:metabolism*; D013312:Stress, Physiological; D013438:Sulfhydryl Compounds / Q000378:metabolism*; D013455:Sulfur / Q000378:metabolism
D000596:Amino Acids; D000603:Amino Acids, Sulfur; D013438:Sulfhydryl Compounds; C402172:homoglutathione; D013455:Sulfur; D008715:Methionine; D005978:Glutathione; D003545:Cysteine