Taxonomy of cyanobacteria: the era of change

Until mid-1970s, cyanobacteria have been interpreted as algae despite they differed from other members of this taxonomic group by the absence of cell nucleus (that is currently considered a character of prokaryotic organization). However, when bacteria were reinterpreted as prokaryotes, blue-green algae became reattributed as cyanobacteria, and bacteriologists began to study their cultured strains with microbiology methods. But since these objects did not obey the provisions of bacteriological code (ICNB), the development of their taxonomy had certain problems, especially regarding nomenclature, that could not be solved until early-2010s. Current changes in taxonomy of cyanobacteria result from a general progress in taxonomy of prokaryotes due to the explosive accumulation of 16S rRNA gene sequencing data, particularly of uncultured objects. Advances in the description of cyanobactera are as follows: I) based on polyphasic approach, new taxa ranging from species to order were published; II) “dark” objects demonstrating several types of non-photosynthetic metabolism were described; III) the objects producing red-shifted chlorophylls d and f were published. Advances in the nomenclatu