GH18 domain of Chitinase D (ChiD). ChiD, a chitinase found in Bacillus circulans, hydrolyzes the 1,4-beta-linkages of N-acetylglucosamine in chitin and chitodextrins. The domain architecture of ChiD includes a catalytic glycosyl hydrolase family 18 (GH18) domain, a chitin-binding domain, and a fibronectin type III domain. The chitin-binding and fibronectin type III domains are located either N-terminal or C-terminal to the catalytic domain. This family includes exochitinase Chi36 from Bacillus cereus.

Chitinase [Carbohydrate transport and metabolism].

chitin-binding domain of Chi A1-like proteins. This group contains proteins related to the chitin binding domain of chitinase A1 (ChiA1) of Bacillus circulans WL-12. Glycosidase ChiA1 hydrolyzes chitin and is comprised of several domains: the C-terminal chitin binding domain, an N-terminal and catalytic domain, and 2 fibronectin type III-like domains. Chitinases function in invertebrates in the degradation of old exoskeletons, in fungi to utilize chitin in cell walls, and in bacteria which use chitin as an energy source. Bacillus circulans WL-12 ChiA1 facilitates invasion of fungal cell walls. The ChiAi chitin binding domain is required for the specific recognition of insoluble chitin. although topologically and structurally related, ChiA1 lacks the characteristic aromatic residues of Erwinia chrysanthemi endoglucanase Z (CBD(EGZ)).

Glycosyl hydrolases family 18.

The GH18 (glycosyl hydrolase, family 18) type II chitinases hydrolyze chitin, an abundant polymer of beta-1,4-linked N-acetylglucosamine (GlcNAc) which is a major component of the cell wall of fungi and the exoskeleton of arthropods. Chitinases have been identified in viruses, bacteria, fungi, protozoan parasites, insects, and plants. The structure of the GH18 domain is an eight-stranded beta/alpha barrel with a pronounced active-site cleft at the C-terminal end of the beta-barrel. The GH18 family includes chitotriosidase, chitobiase, hevamine, zymocin-alpha, narbonin, SI-CLP (stabilin-1 interacting chitinase-like protein), IDGF (imaginal disc growth factor), CFLE (cortical fragment-lytic enzyme) spore hydrolase, the type III and type V plant chitinases, the endo-beta-N-acetylglucosaminidases, and the chitolectins. The GH85 (glycosyl hydrolase, family 85) ENGases (endo-beta-N-acetylglucosaminidases) are closely related to the GH18 chitinases and are included in this alignment model.

Crystalstricture of wild-type chitinase from Bacillus cereus NCTU2 [Bacillus cereus],3N12_A Crystal stricture of chitinase in complex with zinc atoms from Bacillus cereus NCTU2 [Bacillus cereus]

Crystalstricture of E145Q chitinase in complex with NAG from Bacillus cereus NCTU2 [Bacillus cereus]

Crystalstricture of E145G/Y227F chitinase in complex with NAG from Bacillus cereus NCTU2 [Bacillus cereus],3N1A_A Crystal stricture of E145G/Y227F chitinase in complex with cyclo-(L-His-L-Pro) from Bacillus cereus NCTU2 [Bacillus cereus]

Crystalstricture of E145Q/Y227F chitinase in complex with NAG from Bacillus cereus NCTU2 [Bacillus cereus]

Crystalstricture of D143A chitinase in complex with NAG from Bacillus cereus NCTU2 [Bacillus cereus]

Exochitinase 1 OS=Streptomyces olivaceoviridis OX=1921 GN=chi01 PE=1 SV=1

Chitinase D OS=Niallia circulans OX=1397 GN=chiD PE=1 SV=4

Probable class II chitinase ARB_00204 OS=Arthroderma benhamiae (strain ATCC MYA-4681 / CBS 112371) OX=663331 GN=ARB_00204 PE=1 SV=2

Chitinase ChiA OS=Flavobacterium johnsoniae (strain ATCC 17061 / DSM 2064 / JCM 8514 / NBRC 14942 / NCIMB 11054 / UW101) OX=376686 GN=chiA PE=1 SV=1

Chitinase OS=Enterococcus faecalis (strain ATCC 700802 / V583) OX=226185 GN=EF_0361 PE=1 SV=1