The Thermal Stabilization of Rubisco Activase in Maize

Maize yield in plantations can decrease by 40% when exposed to 85° F temperature. The enzyme Ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco) is one of the most abundant enzymes on the planet and is involved with the first major steps of photosynthesis. However, without the help of the enzyme Rubisco activase, the sugars formed by Rubisco during carbon fixation would bind to the active site of Rubisco and stop its function. Due to this, Rubisco activase plays a critical role in photosynthesis. However, it is highly thermally unstable. At just a few degrees above the enzyme’s optimal temperature, Rubisco activase denatures, which drastically slows photosynthesis and decreases crop output. As global temperatures increase, this problem becomes more exaggerated, leading to even lower crop yields. The goal of this study is to use site-directed mutagenesis to introduce mutations in maize Rubisco activase and to identify any stabilizing mutations using protein thermal shift assays. These mutations will ultimately be combined to create a stable variant enzyme