Influence of pH and temperature on cellulase activity and stability in Nectria catalinensis

PARDO, A.G. & F. FORCHIASSIN

REVISTA ARGENTINA DE MICROBIOLOGíA

ASOCIACION ARGENTINA MICROBIOLOGIA

Año: 1999 vol. 31 p. 31 - 35

0325-7541

The influence of temperature and pH on the activity and stability of the cellulase system (endoglucanase, exoglucanase and cellobiase) was investigated in Nectria catalinensis. Optimal temperature for the activity of the cellulase system ranged from 50 to 55 °C, with an optimum for stability between 23 °C and 37 °C after a 72 h incubation period. For the different enzymes, maximal activity was registered between pH 4.2-5,8, with pH 4.8 being close to optimal for all stability studies. The activation energy was 4.97 Kcal mol-1 for endoglucanase, 4.37 Kcal mol-1 for exoglucanase and 13.73 Kcal mol-1 for cellobiase. The K(m) and V(max) values were 1.73 mg CMC ml-1 and 0.45 μmol glucose min-1 mg protein-1 for endoglucanase, 0.22 mg microcrystalline cellulose ml-1 and 57.1 nmol glucose min-1 mg protein-1 for exoglucanase, and 2.95 mM cellobiose and 0.17 μmol glucose min-1 mg protein-1 for cellobiase.