2.3.1.122 evolution members of the Ag85 family, Ag85A, Ag85B, and Ag85C, share high sequence and structural homology characterized by an alpha,beta-hydrolase fold and a hydrophobic fibronectin-binding domain. Their active sites are highly conserved, featuring a histidine, aspartic acid or glutamic acid and serine catalytic triad, a hydrophobic tunnel for the lipids and two trehalose binding sites 720516 2.3.1.122 malfunction inhibition of Ag85 protein family enzymes through substrate analogs hinders growth of mycobacteria and inhibition of Ag85C leads to accumulation of trehalose monomycolate -, 718593 2.3.1.122 metabolism glucose causes Mycobacterium avium to down-regulate trehalose dimycolate expression while up-regulating glucose monomycolate. In vitro, the mechanism of reciprocal regulation of trehalose dimycolate and glucose monomycolate involves competitive substrate selection by antigen 85A. The switch from trehalose dimycolate to glucose monomycolate biosynthesis occurs near the physiological concentration of glucose present in mammalian hosts. Furthermore, it is demonstrated that glucose monomycolate is produced in vivo by mcobacteria in mouse lung 704439 2.3.1.122 physiological function inactivation of corynomycoloyl transferase C specifically abolishes the O-modification of the pore-forming proteins PorA and PorH, which is critical for their biological activity -, 736359 2.3.1.122 physiological function the enzyme is responsible for converting trehalose monomycolate to trehalose dimycolate, which contributes to cell wall stability 720070 2.3.1.122 physiological function the mycoloyl transferase activity of antigen 85 (Ag85) protein family, consisting of Ag85A, -B, and -C, generates trehalose dimycolate, an envelope lipid essential for Mycobacterium tuberculosis virulence, and cell wall arabinogalactan-linked mycolic acids -, 718593