Patent Number: 6,251,646

Title: Method for stabilizing nitrilase activity and preserving microbial cells

Abstract: A method for the stabilization of nitrilase activity of unimmobilized or immobilized microbial cells has been developed. The unimmobilized or immobilized microbial cells are stored in an aqueous solution containing from 0.100 M to the saturation concentration of an inorganic salt of bicarbonate or carbonate, including ammonium, sodium and potassium salts of bicarbonate or carbonate. Aqueous suspensions containing at least 100 mM bicarbonate or carbonate limit microbial contamination of the stored enzyme catalyst, as well as stabilize the desired nitrilase activity of the unimmobilized or immobilized cells. Microorganisms which are characterized by an nitrilase activity and are stabilized and preserved by this method include Acidovorax facilis 72-PF-15 (ATCC 55747), Acidovorax facilis 72-PF-17 (ATCC 55745), and Acidovorax facilis 72W (ATCC 55746).

Inventors: Dicosimo; Robert (Rockland, DE), Ben-Bassat; Arie (Newark, DE), Fallon; Robert D. (Elkton, MD)

Assignee: E. I. du Pont de Nemours and Company

International Classification: C12P 13/00 (20060101); C12N 9/96 (20060101); C12N 9/78 (20060101); C12N 11/08 (20060101); C12N 11/04 (20060101); C12N 1/04 (20060101); C12N 11/00 (20060101); C12N 11/10 (20060101); C12N 009/00 (); C12N 009/96 (); C12N 011/04 (); C12N 011/00 (); C12N 001/04 ()

Expiration Date: 06/26/2018