Construction of the bifunctional enzyme cellulase-beta-glucosidase from the hyperthermophilic bacterium Thermotoga maritima.
An artificial bifunctional enzyme, cellulase-beta-glucosidase, was prepared by gene fusion from the hyperthermophilic bacterium Thermotoga maritima MSB8. The fusion protein exhibited both cellulase (Cel5C) and beta-glucosidase (BglB) activity when the bglB gene was fused to downstream of cel5C, but not when cel5C was fused to downstream of bglB. The specific activity of the bifunctional enzyme was 70% lower than that of cellulase or beta-glucosidase. The fusion enzyme was purified, and the MW was estimated as 114 kDa. The fusion enzyme displayed optimum cellulase activity at pH 8.0 and 70 degrees C over 30 min, and optimal beta-glucosidase activity at pH 7.0 and 80 degrees C over 30 min.
Hong
Su-Young
SY
Division of Applied Life Science, Gyeongsang National University, Chinju, Korea.
Lee
Jin-Suk
JS
Cho
Kye-Man
KM
Math
Renukaradhya K
RK
Kim
Yong-Hee
YH
Hong
Sun-Joo
SJ
Cho
Yong-Un
YU
Cho
Soo-Jeong
SJ
Kim
Hoon
H
Yun
Han-Dae
HD
D002480:Cellulase / Q000235:genetics / Q000378:metabolism*; D004591:Electrophoresis, Polyacrylamide Gel; D006863:Hydrogen-Ion Concentration; D008957:Models, Genetic; D016133:Polymerase Chain Reaction; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000378:metabolism*; D013696:Temperature; D020124:Thermotoga maritima / Q000201:enzymology* / Q000235:genetics; D001617:beta-Glucosidase / Q000235:genetics / Q000378:metabolism*
D011993:Recombinant Fusion Proteins; D001617:beta-Glucosidase; D002480:Cellulase