Overexpression, purification and crystallization of the two C-terminal domains of the bifunctional cellulase ctCel9D-Cel44A from Clostridium thermocellum

• Main Author: Najmudin, Shabir
• Publication Date: 2005
• Other Authors: Guerreiro, Catarina I. P. D., Ferreira, Luís M. A., Romão, Maria J., Fontes, Carlos M. G. A., Prates, José A. M.
• Format: Article
• Language: eng
• Source: Repositórios Científicos de Acesso Aberto de Portugal (RCAAP)
• Download full: https://doi.org/10.1107/S1744309105035670
• topic: Biophysics; Structural Biology; Biochemistry; Genetics; Condensed Matter Physics

Clostridium thermocellum produces a highly organized multi-enzyme complex of cellulases and hemicellulases for the hydrolysis of plant cell-wall polysaccharides, which is termed the cellulosome. The bifunctional multi-modular cellulase ctCel9D-Cel44A is one of the largest components of the C. thermocellum cellulosome. The enzyme contains two internal catalytic domains belonging to glycoside hydrolase families 9 and 44. The C-terminus of this cellulase, comprising a polycystic kidney-disease module (PKD) and a carbohydrate-binding module (CBM44), has been crystallized. The crystals belong to the tetragonal space group P43232, containing a single molecule in the asymmetric unit. Native and seleno-l-methionine-derivative crystals diffracted to 2.1 and 2.8 Å, respectively.