Purification and characterization of low molecular weight extreme alkaline xylanase from the thermophilic fungus Myceliophthora thermophila BF1-7

Purification, characterization and partial amino acid sequences of thermo-alkali-stable and mercury ion-tolerant xylanase from Thermomyces dupontii KKU–CLD–E2–3

“… Fungi Mw (kDa) Optimum pH Optimum temperature pH stabilily Thermostability References Thermomyces dupontii KKU–CLD–E2–3 25 9.0 80 °C a 7.0–10.0 a > 70%, 70 °C b This work Thermomyces lanuginosus CSB 288.54 26.2 7.0–75 70 °C 6.5–10.0 50%, 85 °C Li et al 5 Thermomyces aurantiacus var . levisporus KKU–PN–I2–1 27 9.0 60 °C 7.0–9.0 70%, 50 °C Chanwicha et al 13 Myceliophthora thermophila BF1–7 14 12 50 °C 9.0–12.0 56%, 50 °C Boonrung et al 14 Talaromyces thermophilus F1208 21.6 6.5 55 °C 5.5–6.5 55%, 50 °C Li. et al 31 Myceliophthora heterothallica F.2.1.4 NR c 6.0 55 °C 4.5–9.5 50%, 65 °C Ping et al 32 Sporotrichum thermophile 24 5.0 60 °C …”

“…In addition, xylanase activity was significantly activated by Cu 2+ and Mg 2+ at a concentration of 10 mM up to 248% and 259%, respectively. According to Boonrung et al 14 , the purified xylanase from M. thermophila BF1–7 was activated by Cu 2+ , Mg 2+ and Ag + at 1 mM. The observations of Chanwicha et al 13 showed that the xylanase from T. aurantiacus var.…”

“…levisporus KKU–PN–I2–1 was optimally active at 60 °C. The purified xylanase from the thermophilic fungus M. thermophila BF1–7 was 50 °C 14 . In addition, the maximum activity of purified xylanase from T. aurantiacus M–2 was determined at 75 °C 32 .…”

“…This study then provided better value of both K m and V max in comparison to the value previously reported from T. thermophilus ( K m 22.51 mol/L and V max 1.235 µmol/min/mg) 24 , T. aurantiacus var. levisporus KKU-PN-I2-1 ( K m 40.9 mol/L and V max 6.2 µmol/min/mg) 13 , M. thermophila BF1-7 ( K m 9.67 mol/L and V max 5.38 µmol/min/mg) 14 , and T. aurantiacus M-2 ( K m 4.81 mol/L and V max 467.2 µmol/min/mg) 32 .…”

“…The relative activity of enzyme for each substrate were analyzed at optimum temperature for 15 min and measured according to the standard assay conditions with slightly modification described by Seemakram et al 15 . The kinetic experiments were performed at different concentrations of each substrate ranged from 2.5–30 mg/mL 14 in an optimum buffer and incubated with the purified xylanase at optimum temperature for 15 min. The values of Michaelis–Menten constant ( K m ) and maximal reaction velocity ( V max ) were analyzed by the linear regression method describe by Lineweaver and Burk 20 .…”