Cel9M, a new family 9 cellulase of the Clostridium cellulolyticum cellulosome.
A new cellulosomal protein from Clostridium cellulolyticum Cel9M was characterized. The protein contains a catalytic domain belonging to family 9 and a dockerin domain. Cel9M is active on carboxymethyl cellulose, and the hydrolysis of this substrate is accompanied by a decrease in viscosity. Cel9M has a slight, albeit significant, activity on both Avicel and bacterial microcrystalline cellulose, and the main soluble sugar released is cellotetraose. Saccharification of bacterial microcrystalline cellulose by Cel9M in association with two other family 9 enzymes from C. cellulolyticum, namely, Cel9E and Cel9G, was measured, and it was found that Cel9M acts synergistically with Cel9E. Complexation of Cel9M with the mini-CipC1 containing the cellulose binding domain, the X2 domain, and the first cohesin domain of the scaffoldin CipC of the bacterium did not significantly increase the hydrolysis of Avicel and bacterial microcrystalline cellulose.
Belaich
Anne
A
Laboratoire de Bioénergétique et Ingenierie des Protéines, IBSM, Centre National de la Recherche Scientifique, 31 chemin Joseph Aiguier, 13402 Marseille Cedex 20, France. abelaich@ibsm.cnrs-mrs.fr
Parsiegla
Goetz
G
Gal
Laurent
L
Villard
Claude
C
Haser
Richard
R
Belaich
Jean-Pierre
JP
D000595:Amino Acid Sequence; D001426:Bacterial Proteins / Q000737:chemistry / Q000145:classification* / Q000235:genetics / Q000378:metabolism*; D002266:Carboxymethylcellulose Sodium / Q000378:metabolism*; D002480:Cellulase / Q000737:chemistry / Q000145:classification* / Q000235:genetics / Q000378:metabolism*; D003013:Clostridium / Q000201:enzymology* / Q000235:genetics; D008969:Molecular Sequence Data; D015388:Organelles / Q000201:enzymology*; D011994:Recombinant Proteins / Q000235:genetics / Q000378:metabolism; D017422:Sequence Analysis, DNA
D001426:Bacterial Proteins; D011994:Recombinant Proteins; C450429:Cel9M protein, Clostridium cellulolyticum; D002480:Cellulase; D002266:Carboxymethylcellulose Sodium