Partitioning of sulfur between primary and secondary metabolism

• Applicant: Professor Dr. Stanislav Kopriva
• Subject Area: Plant Physiology
• Term: from 2017 to 2021
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 372353760

Sulfur is an essential nutrient in plants, present in a range of essential primary metabolites as well as in numerous secondary compounds. Due to its chemistry, sulfur in the primary metabolites is usually incorporated in a reduced form as a thiol or sulfide, whereas the secondary compounds contain often oxidized sulfur as organic sulfate. We have characterized 4 isoforms of the enzyme adenosine 5´-phosphosulfate (APS) kinase in Arabidopsis as being essential for completion of the life cycle and for synthesis of sulfated secondary products, such as glucosinolates. Our analyses however left several important questions unanswered: (i.) What is the role of redox regulation of APS kinase for control of partitioning of S between primary and secondary metabolism (ii.) Why is APS kinase isoform APK2 alone not capable to sustain growth of Arabidopsis, and (iii.) What is the importance of APS kinase in plant species not producing glucosinolates? This proposal addresses these questions in order to obtain more detailed and more general insights into control of plant sulfur metabolism.

• DFG Programme: Research Grants