Biocatalytically active silCoat-composites entrapping viable Escherichia coli

Area of Science:

• Biotechnology
• Industrial Microbiology
• Biocatalysis

Background:

• Industrial applications demand whole cells with high catalytic activity, manageability, and viability.
• Immobilization is key to achieving these properties under technical conditions.
• Developing effective carrier materials is crucial for successful cell immobilization.

Purpose of the Study:

• To identify carrier materials for efficient adsorptive binding of whole cells.
• To develop advanced silicone-based materials for immobilizing Escherichia coli expressing a carbonyl reductase.
• To evaluate the performance of immobilized cells regarding viability, loading, leaching, and catalytic activity.

Main Methods:

• Identification and characterization of a carrier material for adsorptive binding of Escherichia coli.
• Composite formation of carrier material with hydrophobic and hydrophilized silicone to create silCoat-material and HYsilCoat-material.
• Immobilization of E. coli hosting Candida parapsilosis carbonyl reductase (CPCR2).
• Evaluation of cell loading, viability, leaching, and catalytic activity of immobilized cells.

Main Results:

• Developed silCoat-material and HYsilCoat-material through composite formation with silicone.
• Achieved high cell loading up to 400 mg(E. coli)·g(-1)(carrier) with HYsilCoat-whole cells.
• Demonstrated considerably lower leaching in HYsilCoat-whole cells compared to native immobilizates.
• Observed distinctly increased catalytic activity of SilCoat-whole cells, especially in neat substrate.

Conclusions:

• Silicone-based carrier materials offer efficient immobilization of whole microbial cells.
• The developed materials enhance cell viability, loading capacity, and reduce leaching.
• SilCoat-whole cells exhibit superior catalytic performance in non-aqueous environments, showing promise for industrial biocatalysis.