Candidatus Melainobacteriota

"Candidatus Melainobacteriota" is a monotypic phylum of bacteria that is the sister phylum of the phylum Cyanobacteria (named under the Botanical Code). It has one class Vampirovibrionophyceae.

Vampirovibrio chlorellavorus is the only species of the phylum that has been grown in cell culture. Candidatus species of melainabacteria have been discovered through DNA and RNA sequence analysis of samples from soil, the human gut, and various aquatic habitats such as groundwater. By analyzing genomes of melainabacteria, predictions are possible about their cell structure and metabolic abilities. The deduced structure of the bacterial cell is similar to cyanobacteria in being surrounded by two membranes. It differs from cyanobacteria in its predicted ability to move by flagella (like gram-negative flagella), though some members (e.g. Gastranaerophilales) appear to lack flagella. It is predicted that melainabacteria are not able to perform photosynthesis, but obtain energy by fermentation.