title: Solubilization of cellulosomal cellulases by fusion with cellulose-binding domain of noncellulosomal cellulase engd from Clostridium cellulovorans.
abstract: Clostridium cellulovorans produces a cellulase complex (cellulosome) as well as noncellulosomal cellulases. In this study, we determined a factor that affected the solubility of the cellulosomal cellulase EngB and the noncellulosomal EngD when they were expressed in Escherichia coli. The catalytic domains of EngB and EngD formed inclusion bodies when expressed in E. coli. On the other hand, both catalytic domains containing the C-terminal cellulose-binding domain (CBD) of EngD were expressed in soluble form. Fusion with the CBD of EngD also helped increased the solubility of cellulosomal cellulase EngL upon expression in E. coli. These results indicate that the CBD of EngD plays an important role in the soluble expression of the catalytic domains of EngB, EngL, and EngD. The possible mechanisms of solubilization by fusion of the catalytic domain with the CBD from EngD are discussed.
authors.affiliation: Section of Molecular Biology, University of California, Davis, CA 95616, USA.
authors.forename: Koichiro
authors.initials: K
authors.lastname: Murashima
authors.forename: Akihiko
authors.initials: A
authors.lastname: Kosugi
authors.forename: Roy H
authors.initials: RH
authors.lastname: Doi
mesh_terms: D000595:Amino Acid Sequence; D001665:Binding Sites; D020134:Catalytic Domain; D002480:Cellulase / Q000737:chemistry* / Q000235:genetics* / Q000378:metabolism; D002482:Cellulose / Q000378:metabolism*; D002846:Chromatography, Affinity; D003013:Clostridium / Q000201:enzymology*; D004926:Escherichia coli / Q000235:genetics; D046911:Macromolecular Substances; D008969:Molecular Sequence Data; D017434:Protein Structure, Tertiary; D011993:Recombinant Fusion Proteins / Q000737:chemistry / Q000302:isolation & purification; D016415:Sequence Alignment; D012995:Solubility
chemical_list: D046911:Macromolecular Substances; D011993:Recombinant Fusion Proteins; D002482:Cellulose; D002480:Cellulase