title: Refactoring the Six-Gene Photosystem II Core in the Chloroplast of the Green Algae Chlamydomonas reinhardtii.
abstract: Oxygenic photosynthesis provides the energy to produce all food and most of the fuel on this planet. Photosystem II (PSII) is an essential and rate-limiting component of this process. Understanding and modifying PSII function could provide an opportunity for optimizing photosynthetic biomass production, particularly under specific environmental conditions. PSII is a complex multisubunit enzyme with strong interdependence among its components. In this work, we have deleted the six core genes of PSII in the eukaryotic alga Chlamydomonas reinhardtii and refactored them in a single DNA construct. Complementation of the knockout strain with the core PSII synthetic module from three different green algae resulted in reconstitution of photosynthetic activity to 85, 55, and 53% of that of the wild-type, demonstrating that the PSII core can be exchanged between algae species and retain function. The strains, synthetic cassettes, and refactoring strategy developed for this study demonstrate the potential of synthetic biology approaches for tailoring oxygenic photosynthesis and provide a powerful tool for unraveling PSII structure-function relationships.
authors.affiliation: California Center for Algae Biotechnology Division of Biological Sciences, University of California, San Diego , 9500 Gilman Drive, La Jolla, California 92093-0368, United States.
authors.forename: Javier A
authors.initials: JA
authors.lastname: Gimpel
authors.affiliation: California Center for Algae Biotechnology Division of Biological Sciences, University of California, San Diego , 9500 Gilman Drive, La Jolla, California 92093-0368, United States.
authors.forename: Hussam H
authors.initials: HH
authors.lastname: Nour-Eldin
authors.affiliation: California Center for Algae Biotechnology Division of Biological Sciences, University of California, San Diego , 9500 Gilman Drive, La Jolla, California 92093-0368, United States.
authors.forename: Melissa A
authors.initials: MA
authors.lastname: Scranton
authors.affiliation: California Center for Algae Biotechnology Division of Biological Sciences, University of California, San Diego , 9500 Gilman Drive, La Jolla, California 92093-0368, United States.
authors.forename: Daphne
authors.initials: D
authors.lastname: Li
authors.affiliation: California Center for Algae Biotechnology Division of Biological Sciences, University of California, San Diego , 9500 Gilman Drive, La Jolla, California 92093-0368, United States.
authors.forename: Stephen P
authors.initials: SP
authors.lastname: Mayfield
mesh_terms: D016825:Chlamydomonas reinhardtii / Q000235:genetics* / Q000378:metabolism; D002736:Chloroplasts / Q000235:genetics* / Q000378:metabolism; D003573:Cytochrome b Group / Q000235:genetics; D017353:Gene Deletion; D055786:Gene Knockout Techniques; D005816:Genetic Complementation Test; D005818:Genetic Engineering / Q000379:methods*; D005822:Genetic Vectors; D018745:Genome, Plant; D045332:Photosystem II Protein Complex / Q000235:genetics* / Q000378:metabolism; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism; D015800:Protozoan Proteins / Q000235:genetics; D044444:Scenedesmus / Q000235:genetics; D044446:Volvox / Q000235:genetics
chemical_list: D003573:Cytochrome b Group; D045332:Photosystem II Protein Complex; D010940:Plant Proteins; D015800:Protozoan Proteins; C075418:psbF protein, Chlamydomonas reinhardti
keywords: Chlamydomonas reinhardtii; chloroplast synthetic biology; microalgae genetic engineering; photosynthesis engineering; photosystem II; refactoring