Characterization of a thermostable and acidic-tolerable beta-glucanase from aerobic fungi Trichoderma koningii ZJU-T.
An extreme thermostable and acidic tolerable beta-glucanase was isolated and characterized from aerobic fungi Trichoderma koningii ZJU-T. The optimal reaction temperature and pH for the beta-glucanase were 100 degrees C and pH 2.0, respectively. The beta-glucanase showed increased stability at higher temperatures and lower pH values when compared to other beta-glucanases. The optimum conditions for the beta-glucanase stability were found to be pH 4.0 and 80 degrees C. Even subjected to 100 degrees C for 3 h, beta-glucanase activity did not show significant reduction. Moreover, K(+) significantly enhanced beta-glucanase activity at the concentration of 1 mM, while EDTA and other metal ions such as Mg(2+), Mn(2+), Zn(2+), Ca(2+), Fe(2+), Pb(2+), and Fe(3+) inhibited beta-glucanase activity. Denaturants, including sodium dodecyl sulfate (SDS) and mercaptoethanol, also inhibited beta-glucanase activity at a concentration of 5%. However, in the presence of 7 M urea, residual activity of the beta-glucanase still remained 14.5%.
Wang
J-L
JL
Dept. of Food Science and Nutrition, Zhejiang Univ., Hangzhou 310029, P. R. China.
Ruan
H
H
Zhang
H-F
HF
Zhang
Q
Q
Zhang
H-B
HB
He
G-Q
GQ
Shen
S-R
SR
D000704:Analysis of Variance; D004492:Edetic Acid / Q000378:metabolism; D044644:Endo-1,3(4)-beta-Glucanase / Q000302:isolation & purification / Q000378:metabolism*; D004795:Enzyme Stability / Q000502:physiology; D006358:Hot Temperature; D006863:Hydrogen-Ion Concentration; D008623:Mercaptoethanol / Q000378:metabolism; D008670:Metals / Q000378:metabolism; D011188:Potassium / Q000737:chemistry; D012967:Sodium Dodecyl Sulfate / Q000378:metabolism; D013379:Substrate Specificity / Q000502:physiology; D013696:Temperature; D013997:Time Factors; D014242:Trichoderma / Q000201:enzymology*; D014508:Urea / Q000378:metabolism
D008670:Metals; D012967:Sodium Dodecyl Sulfate; D008623:Mercaptoethanol; D014508:Urea; D004492:Edetic Acid; D044644:Endo-1,3(4)-beta-Glucanase; D011188:Potassium