Mitokraalien

Mitokraalien is a term used in speculative biology and science fiction to describe hypothetical ultra-small organisms that inhabit mitochondria within eukaryotic cells. The term combines mito-, referring to mitochondria, with a suffix that signals a distinct microbial lineage. It is not part of established biological taxonomy.

In the fictional or hypothetical framework, mitokraalien are intracellular residents that can behave as symbionts or parasites. They are imagined to be nanometer- to micrometer-sized entities that interact with mitochondrial membranes and metabolic pathways. They may influence ATP production, respiration efficiency, and the balance of reactive oxygen species. Their life cycles are often tied to the host cell's cycle, and transmission can occur through vertical inheritance during cell division or horizontal transfer during stress or cellular damage. Many depictions emphasize their capacity for rapid adaptation and genetic exchange with the host, including transfer of genes related to energy metabolism.

The concept is used to explore themes such as coevolution, cellular autonomy, and the ethics of manipulating host metabolism. It also serves as a narrative device to explain unusual physiological traits or diseases in fictional worlds. See also endosymbiont, mitochondrion, symbiosis, and the broader study of host–microbe relationships.