Article

Kinetics of improved productivity of β-galactosidase by a cycloheximide-resistant mutant of Kluyveromyces marxianus

National Institute for Biotechnology and Genetic Engineering
Biotechnology Letters (Impact Factor: 1.74). 04/2004; 26(9):741-746. DOI: 10.1023/B:BILE.0000024089.52462.98

ABSTRACT The maximum volumetric productivity of -galactosidase by a Kluyveromyces marxianus mutant, grown on lactose/corn steep liquor medium for 3d, was 150IUl–1h–1 which is twice that of the parent organism. During product formation, mutated cells provided more resistance against thermal inactivation.

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    • "It was also significantly lower than the values on the thermostabilized glucose isomerase system (160–235 kJ/mol) (Converti and Dominguez 2001). The entropy value of thermal inactivation of enzyme formation by mutant cultures was also very low (and had negative symbol) in SSF and was comparable with that for product formation by the thermo-tolerant yeast (Rajoka et al. 2004) but lower than for a thermo-stabilized reaction (Chen and Stites 2001). This suggested that there was negligible disorder up to 45°C in SSF. "
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