An intracellular parasite that infects a wide range of eukaryotes from protozoans to humans. Its genome is the smallest sequenced to date (2.71 Mbp). Its 11 chromosomes range in size from 217 to 315 kbp. The genome has been compacted by the shortening of intergenic spacers and of the genes themselves. For example, 85% of the proteins translated by Encephalitozoon are shorter than the homologous proteins of Saccharomyces, with a relative mean size difference of 15%. E. cuniculi lacks mitochondria but contains genes that have mitochondria-related functions. This suggests that mitochondria were lost during the evolution of its parasitic way of life. See Classification, Protoctista, Microspora; Genome Sizes and Gene Numbers.
Subjects: Genetics and Genomics.