Sukunaarchaeum
| "Candidatus Sukunaarchaeum" | |
|---|---|
| Scientific classification | |
| Domain: | Archaea |
| Kingdom: | incertae sedis |
| Genus: | "Ca. Sukunaarchaeum" Harada et al., 2025[1]
|
| Species: | "Ca. Sukunaarchaeum mirabile"
|
| Binomial name | |
| "Ca. Sukunaarchaeum mirabile" Harada et al., 2025[1]
| |
"Candidatus Sukunaarchaeum mirabile" (provisional name) is a species of archaea of which only the DNA is known, but which already presents several particularities: it is a holoparasite of the dinoflagellate Citharistes regius and is the first known parasitic archaean. Its DNA, the smallest known for an archaeon, codes for only proteins necessary for reproduction.[2]
Discovery and naming
The proposed name for the genus, "Ca. Sukunaarchaeum", is a reference to Sukunabikona ("renowned little lord"), a small Shinto deity associated with hot springs. The specific epithet, mirabile, means "astonishing, admirable, marvelous."[3]
Features
The DNA of "Ca. Sukunaarchaeum mirabile" is a circular molecule comprising 238 kilobase pairs (kbp), less than half the size of the smallest previously known archaeal DNA. This genome lacks almost all recognizable metabolic pathways, and primarily encodes the mechanisms of DNA replication, transcription, and translation.[4] This suggests an unprecedented level of metabolic dependence on the host, a condition that challenges functional distinctions between minimal cellular life and viruses.[5] Unlike viruses, "Ca. Sukunaarchaeum mirabile" has the ability to replicate its DNA, whereas viruses depend completely on their host organisms for replication.[3]
See also
References
- ^ a b Harada, Ryo; Nishimura, Yuki; Nomura, Mami; Yabuki, Akinori; Shiba, Kogiku; Inaba, Kazuo; Inagaki, Yuji; Nakayama, Takuro (2025-05-02). "A cellular entity retaining only its replicative core: Hidden archaeal lineage with an ultra-reduced genome". bioRxiv 10.1101/2025.05.02.651781.
- ^ Wilcox, Christie (June 13, 2025). Microbe with bizarrely tiny genome may be evolving into a virus (Report). doi:10.1126/science.z7ekqxv.
- ^ a b Buehler, Jake (November 24, 2025). "A Cell So Minimal That It Challenges Definitions of Life". Quanta Magazine. Retrieved January 11, 2026.
- ^ Muñoz Velasco, Israel (June 17, 2025). "El hallazgo de Candidatus Sukunaarchaeum mirabile, una Archaea con el genoma más pequeño hasta ahora descubierto – Laboratorio de Genómica Ambiental, Facultad de Ciencias, Universidad Nacional Autónoma de México" [The finding of Candidatus Sukunaarchaeum mirabile, an Archaea with the smallest genome hitherto discovered.] (in Spanish). National Autonomous University of Mexico. Retrieved June 26, 2025.
- ^ Cowing, Keith (May 7, 2025). "Candidatus Sukunaarchaeum Mirabile Is A Novel Archaeon With An Unprecedentedly Small Genome". Astrobiology. Retrieved June 26, 2025.