The thermostability of C10 is enhanced by addition of Ca2+ and CR.

Thermotolerance of the C10 chimera and parental enzymes in the absence of Ca2+ (A), presence of Ca2+ (B), presence of CR (C), and presence of both Ca2+ and CR (D). Purified cellulases (1μg) were pre-incubated in 50 mM sodium acetate buffer (pH 5.0) at different temperatures for 10 min with or without additional Ca2+ 0.05 mM or/and CR 6.25×10−3 mM. The residual enzyme activity was then determined on 1% PASC at pH 5.0 at their optimal temperature for 6 hrs. The 100% value of relative activity refers to the optimal activity of each enzyme without thermal treatment.