The structural basis of Rubisco phase separation in the pyrenoid.

ABSTRACT: Approximately one-third of global CO₂ fixation occurs in a phase-separated algal organelle called the pyrenoid. The existing data suggest that the pyrenoid forms by the phase separation of the CO₂-fixing enzyme Rubisco with a linker protein; however, the molecular interactions underlying this phase separation remain unknown. Here we present the structural basis of the interactions between Rubisco and its intrinsically disordered linker protein Essential Pyrenoid Component 1 (EPYC1) in the model alga Chlamydomonas reinhardtii. We find that EPYC1 consists of five evenly spaced Rubisco-binding regions that share sequence similarity. Single-particle cryo-electron microscopy of these regions in complex with Rubisco indicates that each Rubisco holoenzyme has eight binding s

SUBMITTER: He S 

PROVIDER: S-EPMC7736253 | biostudies-literature | 2020 Dec

REPOSITORIES: biostudies-literature