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)).

The GH18 (glycosyl hydrolases, family 18) type II chitinases hydrolyze chitin, an abundant polymer of N-acetylglucosamine and have been identified in bacteria, fungi, insects, plants, viruses, and protozoan parasites. The structure of this domain is an eight-stranded alpha/beta barrel with a pronounced active-site cleft at the C-terminal end of the beta-barrel.

Glyco_18 domain.

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.

Glycosyl hydrolases family 18.

ChainA, CHITINASE A1 [Niallia circulans]

ChainA, CHITINASE A1 [Niallia circulans]

Structureof the dioxygenase domain of SACTE_2871, a novel dioxygenase carbohydrate-binding protein fusion from the cellulolytic bacterium Streptomyces sp. SirexAA-E [Streptomyces sp. SirexAA-E],4ILV_B Structure of the dioxygenase domain of SACTE_2871, a novel dioxygenase carbohydrate-binding protein fusion from the cellulolytic bacterium Streptomyces sp. SirexAA-E [Streptomyces sp. SirexAA-E]

Structureof Vibrio cholerae chitin de-N-acetylase in complex with acetate ion (ACT) in P 21 [Vibrio cholerae O1 str. NHCC-010F],4NY2_B Structure of Vibrio cholerae chitin de-N-acetylase in complex with acetate ion (ACT) in P 21 [Vibrio cholerae O1 str. NHCC-010F],4NYU_A Structure of Vibrio cholerae chitin de-N-acetylase in complex with acetate ion (ACT) in C 2 2 21 [Vibrio cholerae O1 str. NHCC-010F],4NYY_A Structure of Vibrio cholerae chitin de-N-acetylase in complex with acetate ion (ACT) in P 2 21 21 [Vibrio cholerae O1 str. NHCC-010F],4NYY_B Structure of Vibrio cholerae chitin de-N-acetylase in complex with acetate ion (ACT) in P 2 21 21 [Vibrio cholerae O1 str. NHCC-010F],4NYY_C Structure of Vibrio cholerae chitin de-N-acetylase in complex with acetate ion (ACT) in P 2 21 21 [Vibrio cholerae O1 str. NHCC-010F],4NYY_D Structure of Vibrio cholerae chitin de-N-acetylase in complex with acetate ion (ACT) in P 2 21 21 [Vibrio cholerae O1 str. NHCC-010F],4NZ4_A Structure of Vibrio cholerae chitin de-N-acetylase in complex with 2-(ACETYLAMINO)-2-DEOXY-A-D-GLUCOPYRANOSE (NDG) and zinc ion [Vibrio cholerae O1 str. NHCC-010F],4NZ4_B Structure of Vibrio cholerae chitin de-N-acetylase in complex with 2-(ACETYLAMINO)-2-DEOXY-A-D-GLUCOPYRANOSE (NDG) and zinc ion [Vibrio cholerae O1 str. NHCC-010F],4NZ5_A Structure of Vibrio cholerae chitin de-N-acetylase in complex with 2-(ACETYLAMINO)-2-DEOXY-A-D-GLUCOPYRANOSE (NDG) and cadmium ion [Vibrio cholerae O1 str. NHCC-010F],4NZ5_B Structure of Vibrio cholerae chitin de-N-acetylase in complex with 2-(ACETYLAMINO)-2-DEOXY-A-D-GLUCOPYRANOSE (NDG) and cadmium ion [Vibrio cholerae O1 str. NHCC-010F]

Structureof Vibrio cholerae chitin de-N-acetylase in complex with DI(N-ACETYL-D-GLUCOSAMINE) (CBS) in P 21 [Vibrio cholerae O1 str. NHCC-010F],4NZ1_B Structure of Vibrio cholerae chitin de-N-acetylase in complex with DI(N-ACETYL-D-GLUCOSAMINE) (CBS) in P 21 [Vibrio cholerae O1 str. NHCC-010F],4NZ3_A Structure of Vibrio cholerae chitin de-N-acetylase in complex with DI(N-ACETYL-D-GLUCOSAMINE) (CBS) in P 21 21 21 [Vibrio cholerae O1 str. NHCC-010F],4NZ3_B Structure of Vibrio cholerae chitin de-N-acetylase in complex with DI(N-ACETYL-D-GLUCOSAMINE) (CBS) in P 21 21 21 [Vibrio cholerae O1 str. NHCC-010F],4OUI_A Structure of Vibrio cholerae chitin de-N-acetylase in complex with TRIACETYLCHITOTRIOSE (CTO) [Vibrio cholerae O1 str. NHCC-010F],4OUI_B Structure of Vibrio cholerae chitin de-N-acetylase in complex with TRIACETYLCHITOTRIOSE (CTO) [Vibrio cholerae O1 str. NHCC-010F]

Chitinase A1 OS=Niallia circulans OX=1397 GN=chiA1 PE=1 SV=1

Exoglucanase B OS=Cellulomonas fimi (strain ATCC 484 / DSM 20113 / JCM 1341 / NBRC 15513 / NCIMB 8980 / NCTC 7547) OX=590998 GN=cbhB PE=1 SV=1

Exoglucanase A OS=Cellulomonas fimi (strain ATCC 484 / DSM 20113 / JCM 1341 / NBRC 15513 / NCIMB 8980 / NCTC 7547) OX=590998 GN=cbhA PE=1 SV=1

Poly(3-hydroxybutyrate) depolymerase OS=Ralstonia pickettii OX=329 PE=3 SV=1

Chitinase C OS=Streptomyces lividans OX=1916 GN=chiC PE=2 SV=1