Biophysical Society Thematic Meeting - October 25-30, 2015

Polymers and Self Assembly: From Biology to Nanomaterials Poster Session II

33-POS Board 33 Immobilization of RubisCO by Self-Assembled Nanotubes Yuan Sun, Sriram Satagopan, F. Robert Tabita, Jon Parquette . The Ohio State University, Columbus, USA.

Biology-inspired catalysts, such as ribulose-1,5-bisphosphate carboxylase-oxygenase (RuBisCO), efficiently reduce CO 2 resulting in products that are subsequently metabolized to energy-rich compounds like glucose by the sequential action of multiple enzymes. However, the use of free or cell-based enzymes as biocatalysts for large-scale industrial processes pose significant limitations due to their incompatibility with reaction conditions that often depart from their physiological states. Although biological catalysts, such as RubisCO, are among the most efficient and ubiquitous catalysts for CO 2 fixation, the use of free or cell-based enzymes as biocatalysts for large-scale industrial processes pose significant drawbacks due to their incompatibility with reaction conditions that often depart from their physiological states. However, cells often compartmentalize various biological reactions to address challenges such as the toxicity of accumulating intermediates, competing reaction pathways and slow turnover rates. Objective : In this work, we attempt to mimic biological compartmentalization, where structures such as carboxysomes naturally encapsulate RubisCO and carbonic anhydrase and provide a protected environment to maximize CO 2 assimilation. Methods : To initiate such studies, we have attempted to encapsulate RubisCO within self-assembled nanotubes. Conditions were established such that RubisCO was successfully sequestered into a variety of self-assembling nanotubes. Results : The encapsulated protein was enzymatically active and was clearly associated with the nanotubes and removed from solution based on a number of criteria. Conclusion : These nanostructures were also found to enhance the stability of RubisCO toward proteases and other environmental factors. We expect this research will permit encapsulated biocatalysts to be useful in scalable CO 2 conversions and other processes.

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