Acts as a chaperone, as it has a significant ability to suppress the thermal denaturation of alcohol dehydrogenase. Cells overexpressing this gene grow more slowly than wild-type cells, and are less susceptible to autolysis following saturation of the culture in vitro, suggesting this protein may slow down the growth rate of M.tuberculosis in culture and by extension during macrophage infection. Probably the external side of the cell wall; the protein is very abundant in older organisms and surface coating could be the result of autolysis of older organisms. Induced by several reactive nitrogen intermediates including S-nitroso glutathione (at protein level). Induced in stationary phase (at protein level). A member of the dormancy regulon. Induced in response to reduced oxygen tension (hypoxia) (at protein level), low levels of nitric oxide (NO) and carbon monoxide (CO). It is hoped that this regulon will give insight into the latent, or dormant phase of infection. Induced in mouse lungs at the same time that adaptive host immunity induces bacterial growth arrest; induction is dependent on interferon gamma. A member of the probable hspX-Rv2030c-pfkB-Rv2028c operon. Multiple forms of this protein exist in 2D-gels. The differences between them has not been examined. Strains deleted for this gene show hypervirulence upon intravenous inoculation in BALB/c mice. In plasmid DNA-vaccinated mice, subsequent challenge with this protein induces positive levels of antigen-specific IFN-gamma and IL-2, indicating this might be a good vaccine candidate. Belongs to the small heat shock protein (HSP20) family.