A red alga about 2 mμ in diameter that inhabits sulfate-rich hot springs (pH 1.5, 45° C). The whole-genome shotgun (WGS) assembly (q.v.) method has been used to determine its nuclear genome. This contains 16,520,305 bp of DNA distributed among 20 chromosomes. The genome is unique in that only 26 of its 5,331 genes contain introns. C. merolae has the smallest genome of all photosynthetic eukaryotes so far studied. This protoctist also has the smallest set of rRNA genes known for any eukaryote. Each cell contains one mitochondrion and one chloroplast. Both organelles have had their DNAs sequenced, and the mitochondrion contains 32,211 bp and the chloroplast 149,987 bp of DNA. See Classification, Protoctista, Rhodophyta; Chronology, Matsuzaki et al.; Genome Sizes and Gene Numbers; division rings, dynamin.
Subjects: Genetics and Genomics.