Phosphatase with a broad specificity. Can dephosphorylate a variety of substrates including phosphorylated sugars like fructose-6-phosphate (F6P) (PubMed:16672613). Is able to function in vivo as a fructose-1,6-bisphosphatase (FBPase) and to maintain gluconeogenesis when the classical FBPase GlpX is absent (PubMed:26258286). Shows negligible phosphoglycerate mutase activity (PubMed:16672613). Has no phosphatase activity against 3-phosphoglycerate, 2,3-bisphosphoglycerate, or hydrophobic substrates such as alpha-napthyl phosphate (PubMed:16672613). a phosphate monoester + H2O = an alcohol + phosphate beta-D-fructose 1,6-bisphosphate + H2O = beta-D-fructose 6-phosphate + phosphate In contrast to classical FBPases, is resistant to inhibition by lithium. kcat is 0.00071 sec(-1) for phosphoglycerate mutase activity (PubMed:16672613). The enzyme's FBPase activity does not follow Michaelis-Menten kinetics but follows allosteric sigmoidal kinetics that show lower affinity for FBP compared with GlpX, but the enzyme's higher turnover number makes it a robust FBPase at high FBP concentrations (PubMed:26258286). Optimum pH is 5.4 for phosphatase activity using pNPP as the substrate. Carbohydrate biosynthesis; gluconeogenesis. Homodimer. Cells lacking both glpX and gpm2 grow as well as wild-type on glucose, but are unable to grow on any of the gluconeogenic carbon sources tested (glycerol, acetate and butyrate); the growth defect on gluconeogenic carbon sources is fully complemented by restoring expression of either GlpX or Gpm2. This double mutant lacks detectable FBPase activity and accumulates FBP. It is also severely attenuated in a mouse model of infection, as it fails to replicate in mouse lungs during the first 10 days of infection and begins to die thereafter. Gluconeogenesis is critical to M.tuberculosis ability to establish infection and is necessary for its survival in the host. Belongs to the phosphoglycerate mutase family.