M. Erra-pujada et al., Purification and properties of the catalytic domain of the thermostable pullulanase type II from Thermococcus hydrothermalis, BIOTECH LET, 23(16), 2001, pp. 1273-1277
A pullulanase type II was produced in Escherichia coli using the relevant g
ene from Thermococcus hydrothermalis. This protein was purified and its pul
lulanolytic and amylolytic activities were characterised. The optimum tempe
rature and Ca2+ concentration for each activity were identical (105 degrees
C and 0.09 mM), whereas the optimum pH (pH(pullulan) 5.75, pH(amylose) 5) a
nd the influence of Ca2+ ions on the kinetic parameters were different. Fur
ther analyses revealed that this enzyme exhibits an endo-processive-like ac
tion and specifically cleaves alpha -1,6 bonds in pullulan.