Research

Amina Jama

Enhancing photosynthesis through molecular manipulation

Amina Jama - 3rd year PhD

Abstract

Enhancing crop yields: The agri-science sector is under great pressure to develop novel tools to increase crop productivity, with increasing photosynthetic efficiency being a major target. Rubisco is a large multimeric enzyme, responsible for the fixation of almost all carbon in the biosphere. It is surprisingly inefficient, and suggested to be a major bottleneck limiting photosynthetic efficiency and crop yield. It suffers from poor substrate specificity, slow catalytic rate and side-reactions generating inhibitory products. Rubisco is regulated by interactions with other proteins e.g. a chaperone Rubisco Activase (RCA), which has a catalytic role and also aids removal of inhibitors from Rubisco’s active site. Structural information is available for both Rubisco and RCA, but not in their complexed (Rubisco/RCA) form, and the mode of interaction is not known. This knowledge could provide insight, needed to enhance the RCA-Rubisco interaction, leading to efficiency improvements that would have a significant impact upon crop yields.

Project Aim: Existing computational methods are not capable of simulating a complex of the magnitude of Rubisco-RCA. We will develop a novel chemical biology theoretical tool, which would offer the technological toolkit, able to tackle this challenge and reveal “hotspots” involved in the interaction on the surface of both enzymes. The results will feed directly into biochemical studies, enabling, for the first time, informed site directed modifications to be made to the surface of RCA, which will perturb the interaction, either enhancing or de-stabilising it in a known and controlled manner. The computational and biochemical studies will be employed iteratively, and the complexes formed will be investigated using biochemical and structural biology tools and assays, to confirm and perturb the mode of interaction. This project is targeted towards enhancing photosynthetic efficiency, a key challenge for the agri-science sector, which is under worldwide pressure to increase crop productivity to cater for society’s growing requirements.