Max Harman

Date: March 19, 2024

Time: 12:00 pm

In-person location: 168 PLB

Zoom: https://bit.ly/prltuesnoon
Meeting ID: 957 9659 6975
Passcode: 420205

Speaker: Max Harman

Lab: Walker lab

Title: Uncapping carbon capture: Elucidating and engineering triose phosphate utilization – the “ceiling” of photosynthesis

Abstract: Gas exchange models of C₃ photosynthesis describe three biochemical limitations governing net CO₂ assimilation. The first two, rubisco carboxylation and RuBP regeneration, occur under low-to-ambient CO₂ concentrations and have been the subjects of extensive study. Higher CO₂ concentrations (and/or low temperature), however, induce sink limitations collectively termed triose phosphate utilization (TPU) limitation, who’s mechanisms remain much less understood. We’ve employed a novel high-throughput chlorophyll fluorescence imaging approach to screen over 1000 EMS-mutagenized Arabidopsis thaliana lines and identified several promising mutants with aberrative TPU phenotypes. We also present preliminary work using Agrobacterium-mediated transient transformation to test reverse genetics hypothesis in engineering the limits of TPU. As atmospheric CO₂ levels continue to increase, TPU looms as both a present and approaching “ceiling” to photosynthesis. This work will aid in contextualizing the impacts of climate change on photosynthetic capacity and inform rational-design crop improvement strategies for carbon sequestration and photosynthetic output.