IUBMB Enzyme Nomenclature


Accepted name: protein-Nπ-phosphohistidine—D-cellobiose phosphotransferase

Reaction: [protein]-Nπ-phospho-L-histidine + D-cellobiose[side 1] = [protein]-L-histidine + D-cellobiose 6'-phosphate[side 2]

Other name(s): celB (gene name); D-cellobiose PTS permease; EIICel; Enzyme IICel

Systematic name: protein-Nπ-phospho-L-histidine:D-cellobiose Nπ-phosphotransferase

Comments: This enzyme is a component (known as enzyme II) of a phosphoenolpyruvate (PEP)-dependent, sugar transporting phosphotransferase system (PTS). The system, which is found only in prokaryotes, simultaneously transports its substrate from the periplasm or extracellular space into the cytoplasm and phosphorylates it. The phosphate donor, which is shared among the different systems, is a phospho-carrier protein of low molecular mass that has been phosphorylated by EC (phosphoenolpyruvate—protein phosphotransferase). Enzyme II, on the other hand, is specific for a particular substrate, although in some cases alternative substrates can be transported with lower efficiency. The reaction involves a successive transfer of the phosphate group to several amino acids within the enzyme before the final transfer to the substrate.

Links to other databases: BRENDA, EXPASY, KEGG, MetaCyc, CAS registry number:


1. Lai, X. and Ingram, L.O. Cloning and sequencing of a cellobiose phosphotransferase system operon from Bacillus stearothermophilus XL-65-6 and functional expression in Escherichia coli, J. Bacteriol. 175 (1993) 6441-6450. [PMID: 8407820]

2. Lai, X., Davis, F.C., Hespell, R.B. and Ingram, L.O. Cloning of cellobiose phosphoenolpyruvate-dependent phosphotransferase genes: functional expression in recombinant Escherichia coli and identification of a putative binding region for disaccharides. Appl. Environ. Microbiol. 63 (1997) 355-363. [PMID: 9023916]

3. Stoll, R. and Goebel, W. The major PEP-phosphotransferase systems (PTSs) for glucose, mannose and cellobiose of Listeria monocytogenes, and their significance for extra- and intracellular growth. Microbiology 156 (2010) 1069-1083. [PMID: 20056707]

4. Wu, M.C., Chen, Y.C., Lin, T.L., Hsieh, P.F. and Wang, J.T. Cellobiose-specific phosphotransferase system of Klebsiella pneumoniae and its importance in biofilm formation and virulence. Infect. Immun. 80 (2012) 2464-2472. [PMID: 22566508]

[EC created 1972 as EC, part transferred 2016 to EC]

Return to EC 2.7.1 home page
Return to EC 2.7 home page
Return to EC 2 home page
Return to Enzymes home page
Return to IUBMB Biochemical Nomenclature home page