S. Karita et al., PURIFICATION OF THE RUMINOCOCCUS-ALBUS ENDOGLUCANASE-IV USING A CELLULOSE-BINDING DOMAIN AS AN AFFINITY TAG, Journal of fermentation and bioengineering, 84(4), 1997, pp. 354-357
The gene encoding the single cellulose-binding domain II (CBD II) of C
lostridium stercorarium xylanase A was fused to the egIV gene encoding
endoglucanase IV (EGIV) from Ruminococcus albus. The fusion protein (
EGIV + CBDII) expressed in Escherichia coli can be readily purified fr
om the cell-free extract of E. coli in a single step using the affinit
y of CBD to cellulose. The purified enzyme was cleaved into two moieti
es, i.e. the catalytic-domain and CBD, at a specific site in the linke
r region by partial digestion with trypsin at 4 degrees C. This result
indicates that this CBD belonging to family VI of CBD families can be
used as an affinity tag for purification of the recombinant protein.