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DOE OSTI · 1779747

Probing photosynthesis by altering chloroplast proteins (Final Technical Report)

Hanson, Maureen R.·Lin, Myat T.
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Abstract

The goal of this project was to explore the effect of altering the carbon fixing enzyme Rubisco in the model C3 plant tobacco on photosynthesis and plant growth and development. We introduced the gene sequences encoding Rubisco from a Limonium species and from a red alga into tobacco and found that the enzyme did not assemble properly, undoubtedly requiring additional assembly factors from the source organism. We then developed a method to make single amino-acid changes into the Rubisco subunit that is encoded by the chloroplast genome. We used the method to investigate the role of particular amino acid residues in kinetic properties of Rubisco. Finally, we improved a bacterial expression system that has allowed assembly of active tobacco Rubisco in E. coli. We used the improved system to investigate the kinetic properties of Rubisco enzymes that contain only one type of Rubisco small subunit along with the large subunit.

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59 BASIC BIOLOGICAL SCIENCEScarbon fixationchloroplast transformationmutantphotosynthesisRubiscotobacco

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Hanson, Maureen R., Lin, Myat T.. 2021-04-28. Probing photosynthesis by altering chloroplast proteins (Final Technical Report). https://doi.org/10.2172/1779747

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