[Nomenclature of obligate methylotrophs]

The nomenclature of obligate methylotrophs, i. e. bacteria using only reduced monocarbon compounds (methane, methanol, methylamines) as a carbon source, is dicussed. The chronology of naming taxons of methane oxidizing bacteria is presented and the rightfulness of their names is analyzed according to the rules of the International Codex of Bacterial Nomenclature. Such names as Methylomonas and others which are employed while describing various physiological groups of bacteria are used in the nomenclature of obligate methylotrophs, and this may be the source of errors. Therefore, only the genus of methane oxidizing bacteria should be referred to as Methylomonas whereas obligate methanol and methylamine assimilating bacteria should be classed as individual genera. The described species of methane oxidizing bacteria can be included into the genera Methylomonas, Methylococcus, Methylosinus, and Methylocystis. One should avoid such names as Methanomonas margaritae, Methanomonas immobilis, Pseudomonas methanica etc. since they do not possess the nomenclature status. All bacteria that depend obligatorily on the presence of reduced C1-compounds should be included into the family Methylomonadaceae. The taxonomy and nomenclature of facultative methylotrophs must be based on principles accepted for other organotrophic microorganisms as it has been suggested at the II International Symposium on the Growth of Microorganisms on C1-compounds (Pushchino, USSR, 1977).