title: [Metastable phenotype of bacteria].
abstract: This review analyzes data available in the literature and the author's own data on the phenotypic variability of bacteria that occurs within the framework of a genotype unchanging in terms of the genetic information stored. This variability is a form of bacterial adaptation to an unstable environment and results from a specific form of natural selection. This phenomenon arose evolutionarily not as a mechanism to provide genetic diversity for the divergence process but as a mechanism of species stabilization; therefore, it was termed phenotype metastability. It includes, as specific variants, processes known as phase and antigenic variations, R-S-M dissociation, phenotype conversion, etc. The mechanisms of phenotype metastability are extremely diverse. They include alternative expression (of the switch on-switch off type) of individual genes or small groups of genes; variation in the composition of synthesized proteins controlled at the level of transcription; expression of complex phenotypes adapted to different environmental conditions that involves phage transposition, reading-frame-shift mutations, etc. The phenomenon of phenotype metastability is widespread among bacteria.
authors.affiliation: Institute of Biochemistry and Physiology of Microorganisms, Russian Academy of Sciences, Pushchino, Moscow, Russia.
authors.forename: E L
authors.initials: EL
authors.lastname: Golovlev
mesh_terms: D000942:Antigens, Bacterial / Q000235:genetics; D001419:Bacteria / Q000235:genetics* / Q000276:immunology; D015964:Gene Expression Regulation, Bacterial; D005798:Genes, Bacterial; D010641:Phenotype
chemical_list: D000942:Antigens, Bacterial
vernacular_title: Metastabil'nost' fenotipa u bakteriĭ.