IUBMB Enzyme Nomenclature


Accepted name: exo-chitinase (non-reducing end)

Reaction: Hydrolysis of N,N'-diacetylchitobiose from the non-reducing end of chitin and chitodextrins.

Other name(s): chiB (gene name)

Systematic name: (1→4)-2-acetamido-2-deoxy-β-D-glucan diacetylchitobiohydrolase (non-reducing end)

Comments: The enzyme hydrolyses the second glycosidic (1→4) linkage from non-reducing ends of chitin and chitodextrin molecules, liberating N,N'-diacetylchitobiose disaccharides. cf. EC, exo-chitinase (reducing end).

BRENDA, EXPASY, KEGG, MetaCyc, PDB, CAS registry number:


1. Tanaka, T., Fukui, T. and Imanaka, T. Different cleavage specificities of the dual catalytic domains in chitinase from the hyperthermophilic archaeon Thermococcus kodakaraensis KOD1. J. Biol. Chem. 276 (2001) 35629-35635. [PMID: 11468293]

2. Hult, E.L., Katouno, F., Uchiyama, T., Watanabe, T. and Sugiyama, J. Molecular directionality in crystalline β-chitin: hydrolysis by chitinases A and B from Serratia marcescens 2170. Biochem. J. 388 (2005) 851-856. [PMID: 15717865]

3. Ohnuma, T., Numata, T., Osawa, T., Mizuhara, M., Lampela, O., Juffer, A.H., Skriver, K. and Fukamizo, T. A class V chitinase from Arabidopsis thaliana: gene responses, enzymatic properties, and crystallographic analysis. Planta 234 (2011) 123-137. [PMID: 21390509]

4. Gutierrez-Roman, M.I., Dunn, M.F., Tinoco-Valencia, R., Holguin-Melendez, F., Huerta-Palacios, G. and Guillen-Navarro, K. Potentiation of the synergistic activities of chitinases ChiA, ChiB and ChiC from Serratia marcescens CFFSUR-B2 by chitobiase (Chb) and chitin binding protein (CBP). World J Microbiol Biotechnol 30 (2014) 33-42. [PMID: 23824666]

[EC created 2017]

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