Open AccessAnalysis of a cellodextrinase cloned from Ruminococcus flavefaciens FD‐1
Author(s) -
Brown G.D.,
Jorgensen T.,
Morris E.J.,
Thomson J.A.
Publication year - 1993
Publication title -
fems microbiology letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.899
H-Index - 151
eISSN - 1574-6968
pISSN - 0378-1097
DOI - 10.1111/j.1574-6968.1993.tb06361.x
Subject(s) - cellobiose , cellulase , escherichia coli , chemistry , hydrolysis , biochemistry , ruminococcus , enzyme , divalent , gene , microbiology and biotechnology , biology , organic chemistry , gut flora
A cellulase gene from Ruminococcus flavefaciens FD‐1 had previously been cloned in Escherichia coli . The product of this gene, CelA, was purified from E. coli and characterised. This 39 kDa cellulase is antigenically related, and of similar mass, to a protein in R. flavefaciens . The enzyme has cellodextrinase activity with predominantly exo‐type action. CelA activity was optimal at pH 6.5 and 41°C, and was inhibited in the presence of divalent metal cations. The K m and V max were determined as 0.68 mM and 1.89 μmol min −1 mg −1 of CelA, respectively. Cellobiose was the major end product of cellodextrin hydrolysis, and our results suggest that celluboise is competitive inhibitor of CelA.