Figure 1

Identification of the genes involved in oligosaccharide uptake and Bgl-dependent utilization in M. mycoides subsp. mycoides SC. (A) Genetic map of the locus involved in the metabolism of β-D-glucosides. The open box indicates the IS element IS1296 and the large horizontal arrows indicate open reading frames found in the 9.8 kb DNA portion. (B) Model for the Bgl-dependent metabolism of β-D-glucosides in M. mycoides subsp. mycoides SC. Oligosaccharides are incorporated into the mycoplasma through the protein EIIBC. Once in the cytoplasm, sugar hydrolase may split complex β-D-glucosides into less complex β-D-glucosides (e.g., monosaccharides and disaccharides). Phosphorylation of these intracellular sugar molecules is preceded by the transfer of a phosphoryl group (P) from phosphoenolpyruvate (PEP) to EIIA in a pathway also involving enzyme I (EI) and the phosphoryl carrier protein (HPr). Then, Bgl hydrolyzes β-glycosidic linkages in the phospho-β-D-glucosides and residual monosaccharides are phosphorylated by the sugar kinase (Suk) before entering glycolysis.