Lepib

Lepib is a fictional term used in speculative biology and science fiction to describe a minimal unicellular organism with a lipid-rich envelope. The concept originated in fictional works and has been adopted by educational simulations to illustrate ideas about cell membranes and genome minimalism.

In described depictions, lepib cells are small, typically about 0.5 to 2 micrometers in diameter. They lack a rigid cell wall and are enclosed by a flexible, protein-rich lipid membrane. Their genomes are compact, encoding essential replication and maintenance functions, with many peripheral processes supplied by the environment or host organisms. Energy metabolism is portrayed as versatile, with some depictions showing either chemoorganoheterotrophy or facultative photosynthesis.

Life cycle and ecology: Lepib reproduce by simple binary fission, producing two daughter cells. They are imagined to inhabit extreme or nutrient-poor environments such as hydrothermal vents, hypersaline lakes, or cooling-water systems, where their membrane flexibility aids survival. In some narratives, lepib participate in microbial communities by exchanging metabolites and forming biofilms.

Significance and cautions: Lepib serves as a thought experiment about minimal cellular design, membrane diversity, and early life scenarios. It is not an established taxon and has no verified existence in the natural world; readers should treat it as fictional. See also speculative biology, minimal genome, protocells.