The N-terminal 160 or 267 residues of xylanase A from Pseudomonas fluorescens subsp. cellulosa, containing a non-catalytic cellulose-binding domain (CBD), were fused to the N-terminus of the catalytic domain of endoglucanase E (EGE') from Clostridium thermocellum. A further hybrid enzyme was constructed consisting of the 347 N-terminal residues of xylanase C (XYLC) from P. fluorescens subsp. cellulosa, which also constitutes a CBD, fused to the N-terminus of endoglucanase A (EGA) from Ruminococcus albus. The three hybrid enzymes bound to insoluble cellulose, and could be eluted such that cellulose-binding capacity and catalytic activity were retained. The catalytic properties of the fusion enzymes were similar to EGE' and EGA respectively. Residues 37-347 and 34-347 of XYLC were fused to the C-terminus of EGE' and the 10 amino acids encoded by the multiple cloning sequence of pMTL22p respectively. The two hybrid proteins did not bind cellulose, although residues 39-139 of XYLC were shown previously to constitute a functional CBD. The putative role of the P. fluorescens subsp. cellulosa CBD in cellulase action is discussed.
Characterization of hybrid proteins consisting of the catalytic domains of Clostridium and Ruminococcus endoglucanases, fused to Pseudomonas non-catalytic cellulose-binding domains
- Views Icon Views
- Share Icon Share
D M Poole, A J Durrant, G P Hazlewood, H J Gilbert; Characterization of hybrid proteins consisting of the catalytic domains of Clostridium and Ruminococcus endoglucanases, fused to Pseudomonas non-catalytic cellulose-binding domains. Biochem J 1 November 1991; 279 (3): 787–792. doi: https://doi.org/10.1042/bj2790787
Download citation file: