Mycobacterium tuberculosis is a dangerous Actinobacteria infecting nearly one third of the human population. It becomes dormant and phenotypically drug resistant in response to stresses. An important feature of the M. tuberculosis pathogenesis is the prevalence of latent infection without disease, making understanding of the mechanisms used by the bacteria to exist in this state and to switch to metabolically active infectious form a vital problem to consider. M. tuberculosis dormancy is regulated by the three-component regulatory system of two kinases (DosT and DevS) and transcriprional regulator (DevR). DevR activates transcription of a set of genes, which allow the bacteria to survive long periods of anaerobiosis, and may be important for long-term survival within the host during latent infection. The DevR-regulon is studied experimentally in M. tuberculosis and few other phylogenetically close Mycobacteria spp. As many other two-component systems, the devRS operon is autoregulated. However, the mechanism of the dormancy is not completely clear even for these bacteria and there is no data describing the dormancy regulons in other species.

Front: Text describes action on various war fronts: North Africa, Libya, Southern Europe, New Guinea, Solomons, Russia, Aleutians, Far East waters, Madagascar. Large world map is keyed to text and illustrates time zones around the world. Smaller map (3 insets): Invasion of Africa. Photographs: Practice led to invasion -- Tanks land for beach operation -- German planes caught by long-range fighters -- Captured Nazi officers perch on hood of British jeep. Back: Why we fight! Also includes photographs.