Toxoplasma gondii apicoplast thioredoxins (TgATrx)

Two essential Thioredoxins mediate apicoplast biogenesis, protein import, and gene expression in Toxoplasma gondii

https://pubmed.ncbi.nlm.nih.gov/29470517/

Toxoplasma gondii: the model apicomplexan

https://pubmed.ncbi.nlm.nih.gov/15003501/

The apicoplast: now you see it, now you don’t

https://www.ncbi.nlm.nih.gov/labs/pmc/articles/PMC5406208/

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Toxoplasma Gondii
Apicomplexan
Apicoplast

https://www.ibiology.org/microbiology/toxoplasma-gondii/

Since little is known about the Toxoplasma gondii genome, in his second iBiology seminar, Lourido explains how his lab developed CRISPR tools to study apicomplexan biology.

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bacterium M. genitalium, an obligate intracellular parasite whose genome consists of 482 genes comprising 582,970 base pairs, arranged on one circular chromosome (the smallest genome of any known natural organism that can be grown in free culture). They then systematically removed genes to find a minimal set of 382 genes that can sustain life. This effort was also known as the Minimal Genome Project.

Parasites such as Plasmodium and Toxoplasma possess a vestigial plastid homologous to the chloroplasts of algae and plants. The plastid (known as the apicoplast; for apicomplexan plastid) is non-photosynthetic and very much reduced, but has clear endosymbiotic ancestry including a circular genome that encodes RNAs and proteins and a suite of bacterial biosynthetic pathways.

Candidatus Hodgkinia cicadicola is a bacterium that forms a symbiotic relationship with cicadas. It's notable because it uses an alternative genetic code. Its genome is 29 circular chromosomes. Therefore, its genome is segmented and composed of circular double-stranded DNA.

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the bacteria & fungus make circular DNA, possibly together in a symbiotic or symbiogenesis relationship, manufacturing the most complex chemicals, connecting to CRISPR.