Improvement of Laccase Production by Co3Bag1. Enhancing the Bio-Catalytic Performance of the Native Thermophilic LacA via Immobilization in Copper Alginate Gel Beads.

A 32-fold increase in laccase activity production by the thermophilic biomass-degrading fungus Co3Bag1 was achieved when the microorganism was grown on a modified medium containing fructose, sodium nitrate, and copper. A 70 kDa laccase (LacA), produced under the above conditions, was purified, immobilized in copper alginate gel beads, and characterized. LacA, both free and immobilized enzymes, exhibited optimal activity at pH 3.

Improvement of catalytical properties of two invertases highly tolerant to sucrose after expression in Pichia pastoris. Effect of glycosylation on enzyme properties.

Zymomonas mobilis genes encoding INVA and INVB were expressed in Pichia pastoris, under the control of the strong AOX1 promoter, and the recombinant enzymes were named INVAAOX1 and INVBAOX1. The expression levels of INVAAOX1 (1660 U/mg) and INVBAOX1 (1993 U/mg) in P. pastoris were 9- and 7-fold higher than those observed for the native INVA and INVB proteins in Z.