Rubisco, the imperfect winner: it's all about the base

Area of Science:

• Biochemistry
• Enzymology
• Molecular Biology

Background:

• Rubisco's catalytic mechanism involves carbamate formation at a lysine residue and enediol creation.
• Rubisco evolved in high CO2 but faces challenges from O2 competition due to Earth's oxidation events.
• Significant variations in Rubisco's catalytic properties exist, linked to its subunit sequences.

Approach:

• This review focuses on the conserved lysine residue's dual role in Rubisco activation and enediol formation.
• Analysis of catalytic variations across the Rubisco superfamily linked to subunit sequences.
• Investigating the evolutionary strategies Rubisco employed to overcome catalytic imperfections.

Key Points:

• The active site lysine is crucial for both activating Rubisco and abstracting protons to form the reactive enediol.
• Enediol formation is central to Rubisco's catalytic function but also a source of inefficiency.
• Significant catalytic diversity exists within the Rubisco superfamily, correlating with sequence variations.

Conclusions:

• The lysine residue is key to understanding Rubisco's kinetic optimization.
• Rubisco and its associated factors have evolved sophisticated strategies to manage catalytic and activation limitations.
• The enzyme's resilience highlights remarkable evolutionary adaptations to diverse environmental pressures.