Figure 6

Activity profile of CelA-SSO1949-CelA at different pH values and temperatures. (A) The cellulase activity of CelA-SSO1949-CelA was assayed at different pH values. The enzyme (120 ng) was incubated with 1 μM fluorescent cellohexaoside in 100 mM phosphate buffer. (B) Temperature optimum of the chimeric enzyme in 100 mM sodium phosphate buffer (pH 3): After correcting the temperature dependent fluorescence intensity the activity of the hybrid protein was calculated (●). At temperatures above 80°C the enzymatic hydrolysis as determined with end-point determination after 60 s (о). The inset shows the Arrhenius analysis with reciprocal abscissa and logarithmic ordinate. The enzyme works best at 85°C and pH 3.