Abstract: This invention relates to methods for increasing carbon fixation and/or increasing biomass production in a plant, comprising: introducing into a plant, plant part, and/or plant cell one or more heterologous polynucleotides encoding polypeptides having the enzyme activity of succinyl CoA synthetase, 2-oxoglutarate:ferredoxin oxidoreductase, 2-oxoglutarate carboxylase, oxalosuccinate reductase and isocitrate lyase to produce a stably transformed plant, plant part, and/or plant cell expressing the one or more heterologous polynucleotides. The methods further comprise introducing into a plant, plant part or plant cell heterologous polynucleotides encoding polypeptides having the enzyme activity of glyoxylate carboligase and tartronic semialdehyde reductase, and/or heterologous polynucleotides encoding a superoxide reductase from an archaeon species, an aquaporin and/or an inhibitor of cell wall invertase inhibitor.

Abstract: This invention relates to compositions and methods for reducing reactive oxygen species in plants, yeast, algae or bacteria by transforming a plant, yeast or bacteria with a heterologous polynucleotide encoding a superoxide reductase from an archaeon species. The invention also provides methods for protecting a photosynthetic reaction center, for reducing photorespiration and/or for increasing the photosynthetic efficiency of plants or cyanobacteria as well as methods for increasing tolerance to abiotic stress in plants, yeast or bacteria by transforming a plant, yeast, or bacteria with a heterologous polynucleotide encoding a archaeon superoxide reductase. Methods for delaying senescence, reducing lignin polymerization and increasing accessibility of cell wall cellulose to an enzyme in a plant by transforming the plant with a heterologous polynucleotide encoding an archaeon superoxide reductase are also provided.

Abstract: The present invention relates to compositions and methods for stable transformation of green microalgae and for production of transgenic green microalgae and/or cyanobacteria that produce extremophile enzymes as co-products during the growth of the green microalgae and/or cyanobacteria for lipid biofuel production. Thus, the present invention provides nucleic acid constructs and methods of transformation useful in the production of stably transformed green microalgae and/or cyanobacteria expressing extremophile enzymes in combination with lipid production for biofuel.