Figure 4

Optimal temperature (a), thermal stability (b), and thermal inactivation (c) of the purified PbChi74 from P. barengoltzii. The temperature optimum was determined at different temperatures (30-80°C) in 50 mM sodium citrate (pH 4.5). For determination of thermostability, the residual activity was measured in 50 mM sodium citrate (pH 4.5) at 65°C after the enzyme was treated for 30 min at different temperatures. For determination of thermal inactivation, the enzyme was incubated at 65°C (open diamonds), 70°C (solid triangles), 75°C (solid circles), and 80°C (open squares) for 4 h.