Dinoflagellate are a major part of oceanic phytoplankton that use Rubisco form II as a primary enzyme for carbon fixation
[54][14]. The form II has both lower specificity and affinity for carbon dioxide/oxygen. This suggests that they have an advanced mechanism to increase carbon dioxide concentration, since they cannot fix carbon dioxide at lower ambient carbon dioxide concentration
[55][15]. Of the various isomers of carbonic anhydrase (α, β, γ, and δ), δ-carbonic anhydrase has been implicated in lowering carbon dioxide concentration
[54][14]. The enzyme carbonic anhydrase (CA) catalyzes rapid conversion of carbon dioxide and bicarbonate ion
[56][16]. Many dinoflagellates have carbon-concentrating mechanisms (CCMs) to transport carbon into the cell
[54][14]. One of the biggest bio-indicators of global warming is the bleaching of coral reefs. Coral reefs that belong to Kingdom Animalia are a complex system of multiple species belonging to phylum coelenterates. The base of the ecosystem is built upon dinoflagellates that live as intracellular photosynthetic symbionts. Loss of these dinoflagellates is believed to be the primary cause of coral bleaching that eroded 85% of the Great Barrier Reef in Australia in 2016
[57,58][17][18]. How do coral reefs become bleached? A slight change in water temperature (2 °F) disturbs the photosynthetic electron transfer and in the process damages the
PsbA (D1), a photosystem II reaction center protein. This disruption of photosynthesis triggers the bleaching of coral reefs
[59,60,61,62,63][19][20][21][22][23].
While genetically engineering cyanobacteria has some success, engineering genes to improve the carbon fixation in diatoms and dinoflagellates has been a challenge due to the lack of critical gene transformation strategies. Initial studies of transformation using silicon carbide whiskers were suggested, but the experiments were difficult to reproduce
[64,65][24][25]. Experiments with glass beads were performed for transient expressions, but even these were hard to reproduce
[57,66][17][26].
Recent studies showed that the stable transformation of dinoflagellates is reproducibly possible when they bombarded microparticle-containing plasmid-like minicircles that carried chloroplast gene
psbA. They successfully transformed two minicircles providing resistance to chloramphenicol and astrazine and in the process assisting the selection of successful transformants. Inability to stably transform has less to do with the inherent genetics of protists than it has to do with the DNA’s inability to cross the membrane barrier
[57][17].