The effect of whole cell immobilisation on the biotransformation of benzonitrile and the use of direct electric current for enhanced product removal

• Published in: Biotechnology and bioengineering 2005-08, Vol.91 (4), p.436-440
• Main Authors: Mustacchi, Roberta, Knowles, Christopher J., Li, Hong, Dalrymple, Ian, Sunderland, Garry, Skibar, Wolfgang, Jackman, Simon A.
• Format: Article
• Language: English
• Subjects: alginate; Alginates - metabolism; Alginic acid; Aminohydrolases - metabolism; Animals; Anions; Anodes; Benzoic acid; Benzoic Acid - analysis; Benzonitrile; Bioconversions. Hemisynthesis; Biological and medical sciences; Bioreactors - microbiology; Biotechnology; Biotransformation; Capsules - metabolism; carboxylic acids; Cells, Immobilized - metabolism; Electric currents; Electricity; electrokinetics; Electrophoresis - methods; Fundamental and applied biological sciences. Psychology; immobilised biocatalysis; Immobilization; Industrial Microbiology; Kinetics; Methods. Procedures. Technologies; Nitrilase; Nitriles - metabolism; product recovery; Q1; Q2; Rhodococcus - enzymology; Rhodococcus rhodochrous
• ISSN: 0006-3592; 1097-0290
• DOI: 10.1002/bit.20522

The nitrilase of Rhodococcus rhodochrous performs a one‐step biotransformation of nitriles to their corresponding carboxylic acids. Application of a direct electric current moves the charged carboxylic acid towards an anode, across an anion exchange membrane, into a separate compartment. Cells encapsulated within alginate beads (2.9 mm diameter) for protection against the current biotransformed benzonitrile to benzoic acid with a 26% reduction in the biotransformation rate, from 0.054 mmol/min/g dcw with free cells to 0.040 mmol/min/g dcw with immobilised cells. When the electric current was applied, the biotransformation rate increased to 0.047 mmol/min/g dcw and product recovery increased from 19% to 79%. © 2005 Wiley Periodicals, Inc.