Table 11.

Catalytic parameters of T. thermosulfurigenesxylose isomerase at 65°C and T. neapolitana xylose isomerase at 80°C and of their mutant derivativesa

Xylose isomeraseGlucoseXylose
Km (mM)Vmax(U/mg)Kcat(min−1)Kcat/Km Km (mM)Vmax(U/mg)Kcat(min−1)Kcat/Km
T. thermosulfurigenes
 Wild type11012.86405.81221.61,10097.2
 W138F6519.497015.04612.262013.6
 V185T9117.68809.71314.574055.4
 W138F/V185T2919.095032.93615.378032.9
T. neapolitana
 Wild type13914.57375.31114.171764.4
 W138F13315.98086.1138.141031.1
 V185T6220.01,01816.41515.679554
 W138F/V185T5212.764412.51410.453038.9
  • a Data from references 245 and313.