Department of Pharmacy and Biotechnology, University of Bologna, I-40126, Bologna, Italy.
Department of Chemistry Giacomo Ciamician, University of Bologna, I-40126 Bologna, Italy; CIRI Health Sciences and Technologies, University of Bologna, I-40126 Bologna, Italy.
Trends Plant Sci. 2021 Sep;26(9):898-912. doi: 10.1016/j.tplants.2021.03.008. Epub 2021 Apr 20.
Oxygenic phototrophs use the Calvin-Benson cycle to fix CO during photosynthesis. In the dark, glyceraldehyde-3-phosphate dehydrogenase (GAPDH) and phosphoribulokinase (PRK), two enzymes of the Calvin-Benson cycle, form an inactive complex with the regulatory protein CP12, mainly under the control of thioredoxins and pyridine nucleotides. In the light, complex dissociation allows GAPDH and PRK reactivation. The GAPDH/CP12/PRK complex is conserved from cyanobacteria to angiosperms and coexists in land plants with an autoassembling GAPDH that is analogously regulated. With the recently described 3D structures of PRK and GAPDH/CP12/PRK, the structural proteome of this ubiquitous regulatory system has been completed. This outcome opens a new avenue for understanding the regulatory potential of photosynthetic carbon fixation by laying the foundation for its knowledge-based manipulation.
需氧光合作用生物利用卡尔文-本森循环在光合作用过程中固定 CO。在黑暗中，甘油醛-3-磷酸脱氢酶（GAPDH）和磷酸核酮糖激酶（PRK），这两种卡尔文-本森循环的酶，与调节蛋白 CP12 形成无活性复合物，主要受硫氧还蛋白和吡啶核苷酸的控制。在光照下，复合物的解离允许 GAPDH 和 PRK 重新激活。从蓝藻到被子植物，GAPDH/CP12/PRK 复合物是保守的，并且在陆生植物中与自动组装的 GAPDH 共存，该 GAPDH 受到类似的调节。随着最近描述的 PRK 和 GAPDH/CP12/PRK 的 3D 结构，这个普遍存在的调节系统的结构蛋白质组已经完成。这一结果为基于知识的操纵奠定了基础，为理解光合作用碳固定的调节潜力开辟了新途径。
