Purification and characterization of two low molecular weight endoglucanases produced by Penicillium occitanis mutant Pol 6
2005
Chaabouni, S.E. | Mechichi, T. | Limam, F. | Marzouki, N.
Two endoglucanases (EGs), EG A and EG B, were purified to homogeneity from Penicillium occitanis mutant Pol 6 culture medium. The molecular weights of EG A and EG B were 31,000 and 28,000 kDa, respectively. The pI was about 3 for EG A and 7.5 for EG B. Optimal activity was obtained at pH 3.5 for both endoglucanases. Optimal temperature for enzyme activity was 60 °C for EG A and 50 °C for EG B. EG A was thermostable at 60 C and remained active after 1 h at 70° C. EGs hydrolyzed carboxymethylcellulose, phosphoric acid swollen cellulose, and β-glucan efficiently, whereas microcrystalline cellulose (Avicel) and laminarin were poorly hydrolyzed. Only EG B showed xylanase activity. Furthermore, these EGs were insensitive to the action of glucose and cellobiose but were inhibited by the divalent cations Hg2+, Co2+, and Mn2+.
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