<i>In Vivo</i> Directed Evolution of an Ultra-Fast Rubisco from a Semi-Anaerobic Environment Imparts Oxygen Resistance.

ABSTRACT: Carbon dioxide (CO₂) assimilation by the enzyme Ribulose-1,5-bisphosphate Carboxylase/Oxygenase (Rubisco) underpins biomass accumulation in photosynthetic bacteria and eukaryotes. Despite its pivotal role, Rubisco has a slow carboxylation rate (kcatCO2) and is competitively inhibited by oxygen (O₂). These traits impose limitations on photosynthetic efficiency, making Rubisco a compelling target for improvement. Interest in Form II Rubisco from Gallionellaceae bacteria, which comprise a dimer or hexamer of large subunits, arises from their nearly 5-fold higher kcatCO2 than the average Rubisco enzyme. As well as having a fast kcatCO2 (25.8 s ^-1 at 25 °C), we show that Gallionellaceae Rubisco (GWS1B) is extremely sensitive to O₂

SUBMITTER: McDonald JL 

PROVIDER: S-EPMC12247655 | biostudies-literature | 2025 May

REPOSITORIES: biostudies-literature