6ZXT

High resolution crystal structure of chloroplastic ribose-5-phosphate isomerase from Chlamydomonas reinhardtii

Summary for 6ZXT

• Entry DOI: 10.2210/pdb6zxt/pdb
• Descriptor: Ribose-5-phosphate isomerase, SULFATE ION, SODIUM ION, ... (4 entities in total)
• Functional Keywords: ribose-5-phosphate, rossmann fold, enzyme, chloroplast, photosynthese, chlamydomonas, isomerase
• Biological source: Chlamydomonas reinhardtii
• Total number of polymer chains: 2
• Total formula weight: 55990.11

Authors

Le Moigne, T.,Crozet, P.,Lemaire, S.D.,Henri, J. (deposition date: 2020-07-30, release date: 2020-11-04, Last modification date: 2024-01-31)

Primary citation

Le Moigne, T.,Crozet, P.,Lemaire, S.D.,Henri, J.
High-Resolution Crystal Structure of Chloroplastic Ribose-5-Phosphate Isomerase from Chlamydomonas reinhardtii -An Enzyme Involved in the Photosynthetic Calvin-Benson Cycle.
Int J Mol Sci, 21:-, 2020

PubMed Abstract: The Calvin-Benson cycle is the key metabolic pathway of photosynthesis responsible for carbon fixation and relies on eleven conserved enzymes. Ribose-5-phosphate isomerase (RPI) isomerizes ribose-5-phosphate into ribulose-5-phosphate and contributes to the regeneration of the Rubisco substrate. Plant RPI is the target of diverse post-translational modifications including phosphorylation and thiol-based modifications to presumably adjust its activity to the photosynthetic electron flow. Here, we describe the first experimental structure of a photosynthetic RPI at 1.4 Å resolution. Our structure confirms the composition of the catalytic pocket of the enzyme. We describe the homo-dimeric state of the protein that we observed in the crystal and in solution. We also map the positions of previously reported post-translational modifications and propose mechanisms by which they may impact the catalytic parameters. The structural data will inform the biochemical modeling of photosynthesis.

PubMed: 33096784
DOI: 10.3390/ijms21207787

Experimental method

X-RAY DIFFRACTION (1.4 Å)