Reaction: Random endo-hydrolysis of N-acetyl-β-D-glucosaminide (1→4)-β-linkages in chitin and chitodextrins
Glossary: chitin = [(1→4)-β-D-GlcpNAc]n = (1→4)-2-acetamido-2-deoxy-β-D-glucan
Other name(s): ChiC; chitodextrinase (ambiguous); 1,4-β-poly-N-acetylglucosaminidase; poly-β-glucosaminidase; β-1,4-poly-N-acetyl glucosamidinase; poly[1,4-(N-acetyl-β-D-glucosaminide)] glycanohydrolase
Systematic name: (1→4)-2-acetamido-2-deoxy-β-D-glucan glycanohydrolase
Comments: The enzyme binds to chitin and randomly cleaves glycosidic linkages in chitin and chitodextrins in a non-processive mode, generating chitooligosaccharides and free ends on which exo-chitinases and exo-chitodextrinases can act. Activity is greatly stimulated in the presence of EC 1.14.99.53, lytic chitin monoxygenase, which attacks the crystalline structure of chitin and makes the polymer more accesible to the chitinase. cf. EC 3.2.1.202, endo-chitodextrinase.
Links to other databases: BRENDA, EXPASY, KEGG, MetaCyc, PDB, CAS registry number: 9001-06-3
References:
1. Zechmeister, L. and Tóth, G. Chromatographic adsorption of the enzymes of emulsin which act on chitins. Enzymologia 7 (1939) 165-169.
2. Tracey, M.V. Chitinase in some basidiomycetes. Biochem. J. 61 (1955) 579-586. [PMID: 13276340]
3. Fischer, E.H. and Stein, E.A. Cleavage of O- and S-glycosidic bonds (survey). In: Boyer, P.D., Lardy, H. and Myrbäck, K. (Eds), The Enzymes, 2nd edn, vol. 4, Academic Press, New York, 1960, pp. 301-312.
4. Connell, T.D., Metzger, D.J., Lynch, J. and Folster, J.P. Endochitinase is transported to the extracellular milieu by the eps-encoded general secretory pathway of Vibrio cholerae. J. Bacteriol. 180 (1998) 5591-5600. [PMID: 9791107]
5. Francetic, O., Badaut, C., Rimsky, S. and Pugsley, A.P. The ChiA (YheB) protein of Escherichia coli K-12 is an endochitinase whose gene is negatively controlled by the nucleoid-structuring protein H-NS. Mol. Microbiol. 35 (2000) 1506-1517. [PMID: 10760150]
6. Zverlov, V.V., Fuchs, K.P. and Schwarz, W.H. Chi18A, the endochitinase in the cellulosome of the thermophilic, cellulolytic bacterium Clostridium thermocellum. Appl. Environ. Microbiol. 68 (2002) 3176-3179. [PMID: 12039789]
7. Rottloff, S., Stieber, R., Maischak, H., Turini, F.G., Heubl, G. and Mithofer, A. Functional characterization of a class III acid endochitinase from the traps of the carnivorous pitcher plant genus, Nepenthes. J. Exp. Bot. 62 (2011) 4639-4647. [PMID: 21633084]