Enzymes of cysteine synthesis show extensive and conserved modifications patterns that include Nα-terminal acetylation
Biosynthesis of cysteine is a two-step process in higher plants subsequently catalyzed by serine acetyltransferase (SAT) and O-acetylserine (thiol) lyase (OAS-TL) which are present in cytosol, plastids and mitochondria. Recently, the distribution of SAT and OAS-TL in these subcellular compartments w...
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| Main Authors: | , , , , |
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| Format: | Article (Journal) |
| Language: | English |
| Published: |
24 July 2010
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| In: |
Amino acids
Year: 2010, Volume: 39, Issue: 4, Pages: 1077-1086 |
| ISSN: | 1438-2199 |
| DOI: | 10.1007/s00726-010-0694-0 |
| Online Access: | Verlag, Volltext: http://dx.doi.org/10.1007/s00726-010-0694-0 Verlag, Volltext: https://link.springer.com/article/10.1007/s00726-010-0694-0 
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| Author Notes: | Markus Wirtz, Corinna Heeg, Arman Allboje Samami, Thomas Ruppert, Rüdiger Hell |
| Summary: | Biosynthesis of cysteine is a two-step process in higher plants subsequently catalyzed by serine acetyltransferase (SAT) and O-acetylserine (thiol) lyase (OAS-TL) which are present in cytosol, plastids and mitochondria. Recently, the distribution of SAT and OAS-TL in these subcellular compartments was shown to be crucial for efficient cysteine synthesis in Arabidopsis thaliana. In this study, the abundances of OAS-TLs were quantified independently by immunological detection in crude protein extracts and by SAT affinity purification (SAP) of OAS-TL. OAS-TL A and B were evidenced to be the most abundant isoforms in all analyzed tissues, which is consistent with micro array-based transcript analyses. Application of SAP to Arabidopsis revealed significant modification of the major OAS-TL isoforms present in cytosol, plastids and mitochondria into up to seven subspecies. Specific OAS-TL isoforms were found to be differentially modified in the leaves, roots, stem and cell culture. Sulphur deficiency did not alter modification of OAS-TL proteins purified from cell culture that showed the highest complexity of OAS-TL modifications. However, the pattern of OAS-TL modification was found to be stable within an analyzed tissue, pointing not only to a high reproducibility of SAP but likely biological significance of each subspecies. The most abundant OAS-TL subspecies in cytosol and plastids were subject of N-terminal processing followed by acetylation of the newly originated N-terminus. The mode of Nα-terminal acetylation of OAS-TL and its possible biological function are discussed. |
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| Item Description: | Gesehen am 24.05.2017 |
| Physical Description: | Online Resource |
| ISSN: | 1438-2199 |
| DOI: | 10.1007/s00726-010-0694-0 |