|
NISCAIR ONLINE PERIODICALS REPOSITORY (NOPR) >
NISCAIR PUBLICATIONS >
Research Journals >
Indian Journal of Biochemistry and Biophysics (IJBB) >
IJBB Vol.49 [2012] >
IJBB Vol.49(3) [June 2012] >
| Title: | Purification and biochemical characterization of endoglucanase from Penicillium pinophilum MS 20 |
| Authors: | Pol, Dipali
Laxman, R Seeta
Rao, Mala |
| Keywords: | Penicillium pinophilum MS 20
Endoglucanase
Carboxymethyl cellulose
Purification
Biochemical properties |
| Issue Date: | Jun-2012 |
| Publisher: | NISCAIR-CSIR, India |
| Abstract: | Cellulases find increasing prominence in sustainable production of fuel
and feedstock from lignocellulosic biomass. The purification and biochemical
characterization of individual components of cellulase complex is important to
understand the mechanism of their action for the solubilization of crystalline
cellulose. In this study, an extra-cellular endoglucanase isolated from culture
filtrate of Penicillium pinophilum MS 20 was purified to
homogeneity by ammonium sulphate precipitation,
ion-exchange chromatography and gel filtration. The purified endoglucanase
(specific activity 69 U/mg) was a monomeric protein with molecular mass of 42
kDa, as determined by SDS-PAGE. The endoglucanase was active over a broad range
of
pH (4-7) with maximum activity at pH 5 and showed optimum temperature of 50°C.
It retained 100% activity at 50°C for 6 h and half- lives of 4 h and 3 h at
60°C and 70°C, respectively. The kinetic constants for the endoglucanase
determined with carboxymethyl cellulose as substrate were Vmax
of 72.5 U/mg and apparent Km of 4.8 mg/ml. The enzyme also
showed moderate activity towards H3PO4 swollen cellulose
and p-nitrophenyl β-D-glucoside, but no activity towards filter paper,
Avicel and oat spelt xylan. The activity was positively modulated by 47, 32 and
25% in the presence of Co2+, Zn2+ and Mg2+,
respectively to the reaction mixture. The wide pH stability (4-7) and
temperature stability up to 50°C of endoglucanase makes the enzyme suitable for
use in cellulose saccharification at moderate temperature and pH.
|
| Page(s): | 189-194 |
| CC License: |  CC Attribution-Noncommercial-No Derivative Works 2.5 India |
| ISSN: | 0975-0959 (Online); 0301-1208 (Print) |
| Source: | IJBB Vol.49(3) [June 2012]
|
|
