A crosslinked preparation of E. coli beta-D-galactosidase

Area of Science:

• Enzyme Engineering
• Biochemistry
• Industrial Biotechnology

Background:

• Beta-D-galactosidase is a crucial enzyme for lactose hydrolysis.
• Native enzymes often exhibit limitations in stability and activity for industrial applications.
• Crosslinking can improve enzyme properties.

Purpose of the Study:

• To enhance the activity and thermal stability of beta-D-galactosidase from E. coli.
• To evaluate the efficacy of crosslinking agents glutaraldehyde and dimethyl adipimidate (DMA).
• To assess the performance of crosslinked enzyme in continuous lactose hydrolysis.

Main Methods:

• Crosslinking of beta-D-galactosidase using glutaraldehyde and dimethyl adipimidate (DMA).
• Activity assays to compare native and crosslinked enzyme preparations.
• Thermal stability assessments.
• Continuous lactose hydrolysis experiments using milk.

Main Results:

• Crosslinking with glutaraldehyde and DMA yielded enzyme preparations with higher activity than native beta-D-galactosidase.
• Both glutaraldehyde and DMA crosslinking enhanced the thermal stability of the enzyme.
• The DMA-crosslinked enzyme demonstrated significantly better performance in continuous milk lactose hydrolysis.

Conclusions:

• Glutaraldehyde and DMA are effective crosslinking agents for improving beta-D-galactosidase properties.
• Crosslinked beta-D-galactosidase exhibits enhanced stability and activity, making it suitable for industrial processes.
• DMA-crosslinked beta-D-galactosidase offers a superior alternative to the native enzyme for continuous lactose hydrolysis in milk.