Identification of the cellulose-binding domain of Fibrobacter succinogenesendoglucanase F

The cellulose-binding domain (CBD) of Fibrobacter succinogenes endoglucanas e F (EGF) has been determined. The gene encoding EGF (celF) and its derivat ives were expressed in Escherichia coli. We were able to obtain eight recom binant proteins and examine their cellulose binding ability and endoglucana se activity. Because four recombinant proteins, which contain the first N-t erminal reiterated region of EGF, bound to cellulose, the region has been i dentified as the CBD. Although the CBD did not show significant sequence si milarity with any other CBDs. it did show significant similarity with a par t of endoglucanase J (CelJ) of Clostridium thermocellum F1. Moreover, a lar ge part of the C-terminal catalytic region of EGF showed sequence similarit y with alpha-L-arabinofuranosidases of glycosyl hydrolase family 51. (C) 20 00 Federation of European Microbiological Societies. Published by Elsevier Science B.V. All rights reserved.