The phosphoenolpyruvate-dependent sugar phosphotransferase system (PTS), a major carbohydrate active -transport system, catalyzes the phosphorylation of incoming sugar substrates concomitant with their translocation across the cell membrane. The EIIB domain is phosphorylated by phospho-EIIA on a cysteinyl or histidyl residue, depending on the transported sugar. Then, it transfers the phosphoryl group to the sugar substrate concomitantly with the sugar uptake processed by the EIIC domain. To M.genitalium MG129 and M.pneumoniae MPN268.