title: [Formation of nonculturable Mycobacterium tuberculosis and their regeneration].
abstract: Nonculturable cells were found to occur in populations of Mycobacterium tuberculosis cells during the long post-stationary phase. These cells were small (0.6-0.8 micron) ovoid and coccoid forms with intact cell walls and negligible respiratory activity, which allows them to be regarded as dormant cells. Nonculturable cells were characterized by low viability after plating onto solid medium; a minor part of the population of these cells could be cultivated in liquid medium. Cell-free culture liquid of an exponential-phase Mycobacterium tuberculosis culture or the bacterial growth factor Rpf exerted a resuscitating effect, increasing substantially the growth capacity of the nonculturable cells in liquid medium. During resuscitation of nonculturable cells, a transition from ovoid to rodlike cell shape occurred. At early stages of resuscitation, ovoid cells formed small aggregates. The recovery of culturability was associated with the formation of rod-shaped cells in the culture. The data obtained demonstrate the in vitro formation of dormant cells of Mycobacterium tuberculosis, which do not grow on solid media but can be resuscitated in liquid medium under the effect of substance(s) secreted by actively growing cells.
authors.affiliation: Bach Institute of Biochemistry, Russian Academy of Sciences, Leninskii pr. 33, Moscow, 117071 Russia.
authors.forename: M O
authors.initials: MO
authors.lastname: Shleeva
authors.forename: G V
authors.initials: GV
authors.lastname: Mukamolova
authors.forename: M V
authors.initials: MV
authors.lastname: Telkov
authors.forename: T L
authors.initials: TL
authors.lastname: Berezinskaia
authors.forename: A V
authors.initials: AV
authors.lastname: Syroeshkin
authors.forename: S F
authors.initials: SF
authors.lastname: Biketov
authors.forename: A S
authors.initials: AS
authors.lastname: Kaprel'iants
mesh_terms: D018407:Bacterial Physiological Phenomena; D001426:Bacterial Proteins / Q000378:metabolism; D003470:Culture Media; D016207:Cytokines / Q000378:metabolism; D009169:Mycobacterium tuberculosis / Q000166:cytology / Q000502:physiology*
chemical_list: D001426:Bacterial Proteins; D003470:Culture Media; D016207:Cytokines; C113704:resuscitation-promoting factor, bacteria
vernacular_title: Obrazovanie "nekul'tiviruemykh" kletok Mycobacterium tuberculosis i ikh ozhivlenie.