Photosynthesis – The dark side structural proteome is now completed
The crystal structure of the phosphoribulokinase (PRK) – the last enzyme of the Calvin-Benson cycle – has been finally solved, completing its redox structural proteome. The PRK structure also allowed to shed light on the molecular evolution of PRKs in eukaryotes.Gurrieri L. et al., Proceedings of the National Academy of Sciences Mar 2019, 201820639
| The Calvin-Benson cycle is the set of chemical reactions that take place in chloroplasts during photosynthesis. The cycle is light-independent (dark) because it takes place after the energy has been captured from sunlight. It consists of 13 distinct reactions catalysed by 11 enzymes. Among these, the phosphoribulokinase (PRK) had notably still to be characterized at the atomic scale. To accomplish this goal and complete the redox structural proteome of the CB cycle, authors determined the crystal structures of PRK from two model species: the green alga Chlamydomonas reinhardtii (CrPRK) and the land plant Arabidopsis thaliana (AtPRK). Structural comparisons with prokaryotic and evolutionarily older PRKs revealed that both AtPRK and CrPRK have a strongly reduced dimer interface and an increased number of random coiled regions, suggesting a general |
loss in structural rigidity during molecular evolution of PRKs in eukaryotes. Retrieve Article
Arabidopsis and Chlamydomonas phosphoribulokinase crystal structures complete the redox structural proteome of the Calvin–Bensoncycle; |
Ultima modifica il Giovedì, 18 Maggio 2023 14:12
