DB code: M00134

RLCP classification 1.32.5000.73 : Hydrolysis
CATH domain 3.20.20.80 : TIM Barrel Catalytic domain
3.10.50.10 : Chitinase A; domain 3
2.60.40.30 : Immunoglobulin-like
2.60.40.30 : Immunoglobulin-like
2.10.10.20 : Seminal Fluid Protein PDC-109 (Domain B)
E.C. 3.2.1.14
CSA 1itx
M-CSA 1itx
MACiE

CATH domain Related DB codes (homologues)
2.10.10.20 : Seminal Fluid Protein PDC-109 (Domain B) D00501
2.60.40.30 : Immunoglobulin-like M00124 M00129 M00136 M00149 M00192
3.10.50.10 : Chitinase A; domain 3 T00063
3.20.20.80 : TIM Barrel S00202 S00210 S00748 S00906 S00907 S00911 S00912 S00915 M00160 D00479 S00204 S00205 S00206 S00207 S00203 S00208 S00209 S00211 S00213 S00214 M00113 T00307 D00165 D00166 D00169 D00176 D00501 D00502 D00503 D00844 D00861 D00864 M00026 M00112 M00193 M00346 T00057 T00062 T00063 T00066 T00067

Uniprot Enzyme Name
UniprotKB Protein name Synonyms CAZy Pfam
P20533 Chitinase A1
EC 3.2.1.14
CBM12 (Carbohydrate-Binding Module Family 12)
GH18 (Glycoside Hydrolase Family 18)
PF02839 (CBM_5_12)
PF00041 (fn3)
PF00704 (Glyco_hydro_18)
[Graphical View]

KEGG enzyme name
chitinase
chitodextrinase
1,4-beta-poly-N-acetylglucosaminidase
poly-beta-glucosaminidase
beta-1,4-poly-N-acetyl glucosamidinase
poly[1,4-(N-acetyl-beta-D-glucosaminide)] glycanohydrolase

UniprotKB: Accession Number Entry name Activity Subunit Subcellular location Cofactor
P20533 CHIA1_BACCI Random hydrolysis of N-acetyl-beta-D- glucosaminide (1->4)-beta-linkages in chitin and chitodextrins.

KEGG Pathways
Map code Pathways E.C.
MAP00530 Aminosugars metabolism

Compound table
Substrates Products Intermediates
KEGG-id C00461 C00851 C00001 C03518 C00140
E.C.
Compound Chitin Chitodextrin H2O N-Acetyl-D-glucosaminide N-Acetyl-D-glucosamine
Type amide group,polysaccharide amide group,polysaccharide H2O amide group,carbohydrate amide group,carbohydrate
ChEBI 15377
 15377
 		506227
 506227
PubChem 22247451
 962
 22247451
 962
 		439174
 439174
1itxA01 Unbound Unbound Unbound Unbound
1itxA02 Unbound Unbound Unbound Unbound
1k85A Unbound Unbound Unbound Unbound
1ed7A Unbound Unbound Unbound Unbound

Reference for Active-site residues
resource references E.C.
(T00063)

Active-site residues
PDB Catalytic residues Cofactor-binding residues Modified residues Main-chain involved in catalysis Comment
1itxA01 ASP 202;GLU 204;TYR 279;ASP 280
1itxA02
1k85A
1ed7A

References for Catalytic Mechanism
References Sections No. of steps in catalysis
[8]
p.853-854

References
[1]
Resource
Comments MUTAGENESIS.
Medline ID 93366760
PubMed ID 8103047
Journal J Biol Chem
Year 1993
Volume 268
Pages 18567-72
Authors Watanabe T, Kobori K, Miyashita K, Fujii T, Sakai H, Uchida M, Tanaka H
Title Identification of glutamic acid 204 and aspartic acid 200 in chitinase A1 of Bacillus circulans WL-12 as essential residues for chitinase activity.
Related PDB
Related UniProtKB P20533
[2]
Resource
Comments
Medline ID
PubMed ID 7765724
Journal Biosci Biotechnol Biochem
Year 1994
Volume 58
Pages 2283-5
Authors Watanabe T, Uchida M, Kobori K, Tanaka H
Title Site-directed mutagenesis of the Asp-197 and Asp-202 residues in chitinase A1 of Bacillus circulans WL-12.
Related PDB
Related UniProtKB
[3]
Resource
Comments
Medline ID
PubMed ID 8168626
Journal FEBS Lett
Year 1994
Volume 343
Pages 177-80
Authors Armand S, Tomita H, Heyraud A, Gey C, Watanabe T, Henrissat B
Title Stereochemical course of the hydrolysis reaction catalyzed by chitinases A1 and D from Bacillus circulans WL-12.
Related PDB
Related UniProtKB
[4]
Resource
Comments
Medline ID
PubMed ID 8045877
Journal J Bacteriol
Year 1994
Volume 176
Pages 4465-72
Authors Watanabe T, Ito Y, Yamada T, Hashimoto M, Sekine S, Tanaka H
Title The roles of the C-terminal domain and type III domains of chitinase A1 from Bacillus circulans WL-12 in chitin degradation.
Related PDB
Related UniProtKB
[5]
Resource
Comments
Medline ID
PubMed ID 10913612
Journal FEBS Lett
Year 2000
Volume 476
Pages 194-7
Authors Honda Y, Tanimori S, Kirihata M, Kaneko S, Tokuyasu K, Hashimoto M, Watanabe T, Fukamizo T
Title Kinetic analysis of the reaction catalyzed by chitinase A1 from Bacillus circulans WL-12 toward the novel substrates, partially N-deacetylated 4-methylumbelliferyl chitobiosides.
Related PDB
Related UniProtKB
[6]
Resource
Comments X-ray crystallography
Medline ID
PubMed ID 10788483
Journal J Biol Chem
Year 2000
Volume 275
Pages 13654-61
Authors Ikegami T, Okada T, Hashimoto M, Seino S, Watanabe T, Shirakawa M
Title Solution structure of the chitin-binding domain of Bacillus circulans WL-12 chitinase A1.
Related PDB 1ed7
Related UniProtKB
[7]
Resource
Comments
Medline ID
PubMed ID 11297738
Journal FEBS Lett
Year 2001
Volume 494
Pages 74-8
Authors Watanabe T, Ishibashi A, Ariga Y, Hashimoto M, Nikaidou N, Sugiyama J, Matsumoto T, Nonaka T
Title Trp122 and Trp134 on the surface of the catalytic domain are essential for crystalline chitin hydrolysis by Bacillus circulans chitinase A1.
Related PDB 1itx
Related UniProtKB
[8]
Resource
Comments
Medline ID
PubMed ID 11742103
Journal Protein Eng
Year 2001
Volume 14
Pages 845-55
Authors Nagano N, Porter CT, Thornton JM
Title The (betaalpha)(8) glycosidases: sequence and structure analyses suggest distant evolutionary relationships.
Related PDB
Related UniProtKB
[9]
Resource
Comments
Medline ID
PubMed ID 11821923
Journal Curr Microbiol
Year 2002
Volume 44
Pages 167-72
Authors Wiwat C, Thepouyporn A, Siwayaprahm P, Bhumiratana A
Title Cloning, sequencing, and expression of a chitinase-encoding gene from Bacillus circulans No. 4.1.
Related PDB
Related UniProtKB
[10]
Resource
Comments
Medline ID
PubMed ID 11801254
Journal FEBS Lett
Year 2002
Volume 510
Pages 201-5
Authors Imai T, Watanabe T, Yui T, Sugiyama J
Title Directional degradation of beta-chitin by chitinase A1 revealed by a novel reducing end labelling technique.
Related PDB
Related UniProtKB
[11]
Resource
Comments
Medline ID
PubMed ID 11926993
Journal J Biochem (Tokyo)
Year 2002
Volume 131
Pages 557-64
Authors Sasaki C, Yokoyama A, Itoh Y, Hashimoto M, Watanabe T, Fukamizo T
Title Comparative study of the reaction mechanism of family 18 chitinases from plants and microbes.
Related PDB
Related UniProtKB
[12]
Resource
Comments
Medline ID
PubMed ID 11600504
Journal J Biol Chem
Year 2002
Volume 277
Pages 1388-97
Authors Jee JG, Ikegami T, Hashimoto M, Kawabata T, Ikeguchi M, Watanabe T, Shirakawa M
Title Solution structure of the fibronectin type III domain from Bacillus circulans WL-12 chitinase A1.
Related PDB 1k85
Related UniProtKB

Comments
This enzyme belongs to chitinase class-II (glycosyl hydrolase family-18).
This enzyme is composed of N-terminal catalytic domain, two fibronectin type-III domains and C-terminal chitin-binding domain. The PDB structures, 1itx, 1k85, and 1ed7 correspond to the catalytic domain, the second fibronectin type-III domain, and chitin-binding domain, respectively.
According to the literature [8], in glycosylase family-18, there are two types of enzymes with different catalytic mechanisms, chitinase (PDB; 1ctn) and hevamine (2hvm). The former enzyme uses two acidic residue as catalytic residues, whilst the latter has only one catalytic residue, using a moiety of its substrate as a catalytic group during the catalysis. The catalytic domain of this enzyme is similar to chitinase, rather than hevamine, since it has two acidic residues, which can be superimposed to those of chitinase (T00063).
However, more recent study proposed that Tyr279, which is conserved throughout the family-18, instead of Asp280, can be involved in catalysis (T00063).
Although this enzyme has a different domain composition from chitinase, these enzymes must have the same catalytic mechanism.

Created Updated
2004-03-19 2010-12-03