Biochemical characterization of highly organic solvent-tolerant cutinase from Fusarium oxysporum

Biochemical characterization of cuLinase from Fusuriurn oxysporum produced by submerged fermentation indicated that the enzyme showed a significant increase in activity, after exposure for 1 h in organic solvents, especially octanol, 2-nonanol, hexane, octane, isooctane and decane. After exposure to these solvents, the enzyme activity was higher by more than 40% when compared with the control without exposure to organic solvents. The highest activity observed in organic solvents, indicates the great potential of this enzyme in non-aqueous systems. The enzyme retained its activity almost completely in the temperature range between 28 and 50 degrees C, maintaining its activity more than 80% after 1 h at these temperatures. The enzyme retained its activity superior to 50% in the pH range between 5.6 and 7.0 after 24 h at 30 degrees C. The multivariate study showed that the activity is higher at temperature of 28 degrees C and pH 6.0. The enzyme has been activated in most metal ions tested, with the best result observed in the presence of Na+ (1 mM). The enzyme exhibited low activity in the ionic liquids tested (BMIM-PF4, BMIM-PF6). The presence of sodium oxalate, sodium citrate, sodium bisulfite and sodium azide (1 mM), significantly increased the activity of the enzyme, indicating that these salts bind to certain metal ions, which interfere with the action of the enzyme. The biochemical properties observed, indicating the potential of this enzyme for industrial and biotechnological applications. (C) 2013 Elsevier Ltd. All rights reserved.