|Gene:||celQ||Accession Numbers: G-12701 (MetaCyc), Cthe_0625|
Synonyms: endoglucanase Q
The celQ gene of Ruminiclostridium thermocellum is located immediately following the celJ gene. The gene was cloned and sequenced, and found to contain a signal peptide, a family 9 cellulase domain (GH9), a family IIIc carbohydrate binding module (CBM), and a dockerin domain.
A truncated derivative of CelQ consisting of only the catalytic domain and the CBM was constructed and investigated. The truncated protein showed strong activity toward carboxymethyl cellulose and barley β-glucan and low activity toward avicel, acid-swollen cellulose, lichenan, and xylan.
A second mutant that was devoid of the CBM showed negligible activity toward carboxymethyl cellulose, supporting the idea that family IIIc CBMs participate in the catalytic function of the enzyme.
Molecular Weight of Polypeptide: 79.811 kD (from nucleotide sequence)
Relationship Links: CAZy:IN-FAMILY:CBM3 , CAZy:IN-FAMILY:GH9 , InterPro:IN-FAMILY:IPR001701 , InterPro:IN-FAMILY:IPR001956 , InterPro:IN-FAMILY:IPR002105 , InterPro:IN-FAMILY:IPR008928 , InterPro:IN-FAMILY:IPR008965 , InterPro:IN-FAMILY:IPR012341 , InterPro:IN-FAMILY:IPR016134 , InterPro:IN-FAMILY:IPR018221 , InterPro:IN-FAMILY:IPR018242 , InterPro:IN-FAMILY:IPR018247 , Pfam:IN-FAMILY:PF00404 , Pfam:IN-FAMILY:PF00759 , Pfam:IN-FAMILY:PF00942 , Prosite:IN-FAMILY:PS00018 , Prosite:IN-FAMILY:PS00448 , Prosite:IN-FAMILY:PS00592 , Prosite:IN-FAMILY:PS00698 , Prosite:IN-FAMILY:PS51172 , Smart:IN-FAMILY:SM01067
Enzymatic reaction of: cellulase
EC Number: 18.104.22.168
The reaction direction shown, that is, A + B ↔ C + D versus C + D ↔ A + B, is in accordance with the Enzyme Commission system.
The reaction is physiologically favored in the direction shown.
Arai01: Arai T, Ohara H, Karita S, Kimura T, Sakka K, Ohmiya K (2001). "Sequence of celQ and properties of celQ, a component of the Clostridium thermocellum cellulosome." Appl Microbiol Biotechnol 57(5-6);660-6. PMID: 11778875
Gordillo06: Gordillo F, Caputo V, Peirano A, Chavez R, Van Beeumen J, Vandenberghe I, Claeyssens M, Bull P, Ravanal MC, Eyzaguirre J (2006). "Penicillium purpurogenum produces a family 1 acetyl xylan esterase containing a carbohydrate-binding module: characterization of the protein and its gene." Mycol Res 110(Pt 10);1129-39. PMID: 17008082
Schadel10: Schadel C, Richter A, Blochl A, Hoch G (2010). "Hemicellulose concentration and composition in plant cell walls under extreme carbon source-sink imbalances." Physiol Plant 139(3);241-55. PMID: 20113432
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