|Gene:||celD||Accession Numbers: G-12687 (MetaCyc), Cthe_0825|
Synonyms: endoglucanase D
The celD gene of Ruminiclostridium thermocellum encodes one of the best-studied endoglucanases of anaerobic bacteria. It was first cloned in a study where ten distinct EcoRI fragments of Clostridium thermocellum, corresponding to seven different endoglucanases, were cloned in Escherichia coli and shown to express enzymatic activities related to cellulose degradation [Millet85].
The enzyme has been purified from the Escherichia coli host and crystallized, and shown to be a monomeric endoglucanase. The purified enzyme had a very high specific activity with carboxymethyl cellulose (428 IU/mg) [Joliff86].
The celD gene has been sequenced [Joliff86a]. The protein includes a type I dockerin domain that facilitates its binding to one of the type I cohesin domains of the CipA scaffoldin protein, enabling it to become a part of the cellulosome complex [Salamitou94, Kataeva97, GarciaCampayo97, Schaeffer02]. Ca2+-binding, which is essential for the dockerin-cohesin bond formation, has been reported [Chauvaux90, Chauvaux95]. The presence of the dockerin domain encourages over-expressed CelD to form inclusion bodies [Tokatlidis91a, Chaffotte92].
Locations: extracellular space
Molecular Weight of Polypeptide: 72.415 kD (from nucleotide sequence), 65.0 kD (experimental) [Tokatlidis91a ]
Relationship Links: CAZy:IN-FAMILY:GH9 , InterPro:IN-FAMILY:IPR001701 , InterPro:IN-FAMILY:IPR002105 , InterPro:IN-FAMILY:IPR004197 , InterPro:IN-FAMILY:IPR008928 , InterPro:IN-FAMILY:IPR012341 , InterPro:IN-FAMILY:IPR013783 , InterPro:IN-FAMILY:IPR014756 , InterPro:IN-FAMILY:IPR016134 , InterPro:IN-FAMILY:IPR018221 , InterPro:IN-FAMILY:IPR018242 , PDB:Structure:4FL4 , Pfam:IN-FAMILY:PF00404 , Pfam:IN-FAMILY:PF00759 , Pfam:IN-FAMILY:PF02927 , Prosite:IN-FAMILY:PS00018 , Prosite:IN-FAMILY:PS00448 , Prosite:IN-FAMILY:PS00592 , Prosite:IN-FAMILY:PS00698
|Cellular Component:||GO:0005576 - extracellular region|
Enzymatic reaction of: cellulase
EC Number: 126.96.36.199
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.
Chaffotte92: Chaffotte AF, Guillou Y, Goldberg ME (1992). "Inclusion bodies of the thermophilic endoglucanase D from Clostridium thermocellum are made of native enzyme that resists 8 M urea." Eur J Biochem 205(1);369-73. PMID: 1555596
Chauvaux90: Chauvaux S, Beguin P, Aubert JP, Bhat KM, Gow LA, Wood TM, Bairoch A (1990). "Calcium-binding affinity and calcium-enhanced activity of Clostridium thermocellum endoglucanase D." Biochem J 265(1);261-5. PMID: 2302168
Chauvaux95: Chauvaux S, Souchon H, Alzari PM, Chariot P, Beguin P (1995). "Structural and functional analysis of the metal-binding sites of Clostridium thermocellum endoglucanase CelD." J Biol Chem 270(17);9757-62. PMID: 7730353
GarciaCampayo97: Garcia-Campayo V, Beguin P (1997). "Synergism between the cellulosome-integrating protein CipA and endoglucanase CelD of Clostridium thermocellum." J Biotechnol 57(1-3);39-47. PMID: 9335164
Joliff86: Joliff G, Beguin P, Millet J, Aubert JP, Alzari P, Juy M, Poljak RJ (1986). "Crystallization and preliminary X-ray diffraction study of an endoglucanase from Clostridium thermocellum." J Mol Biol 189(1);249-50. PMID: 3783675
Kataeva97: Kataeva I, Guglielmi G, Beguin P (1997). "Interaction between Clostridium thermocellum endoglucanase CelD and polypeptides derived from the cellulosome-integrating protein CipA: stoichiometry and cellulolytic activity of the complexes." Biochem J 326 ( Pt 2);617-24. PMID: 9291140
Millet85: Millet, J., Petre, D., Beguin, P., Raynaud, O., Aubert, J. P. (1985). "Cloning of ten distinct DNA fragments of Clostridium thermocellum coding for cellulases (Endoglucanases, cellobiohydrolases, cellulolytic genes)." FEMS Microbiology Letters 29:145-149.
Salamitou94: Salamitou S, Raynaud O, Lemaire M, Coughlan M, Beguin P, Aubert JP (1994). "Recognition specificity of the duplicated segments present in Clostridium thermocellum endoglucanase CelD and in the cellulosome-integrating protein CipA." J Bacteriol 176(10);2822-7. PMID: 8188583
Schaeffer02: Schaeffer F, Matuschek M, Guglielmi G, Miras I, Alzari PM, Beguin P (2002). "Duplicated dockerin subdomains of Clostridium thermocellum endoglucanase CelD bind to a cohesin domain of the scaffolding protein CipA with distinct thermodynamic parameters and a negative cooperativity." Biochemistry 41(7);2106-14. PMID: 11841200
Tokatlidis91a: Tokatlidis K, Dhurjati P, Millet J, Beguin P, Aubert JP (1991). "High activity of inclusion bodies formed in Escherichia coli overproducing Clostridium thermocellum endoglucanase D." FEBS Lett 282(1);205-8. PMID: 2026260
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