Passivation of nerve agents by surface modified enzymes stabilized by non-covalent immobilization on robust, stable particles

Abstract

Enzymes are modified by incorporating anchor sites for linking the enzymes to a target surface without destroying the catalytic activity of the enzymes. A a stable carrier to accommodate and bind the selected enzyme is constructed, and the enzyme is non-covalently liked to the carrier, generally through metal salts of iminodiacetate

What is claimed is:  
     
         1 . A surface modified enzyme comprising an enzyme genetically engineered to include a stabilizing group at the N-terminus, which stabilizing group is used to immobilize the enzyme onto a polymerized vesicle or inorganic surface.  
     
     
         2 . The surface modified enzyme according to  claim 1  wherein the stabilizing group is selected from the group consisting of histidine and polyhistidine.  
     
     
         3 . A method for stabilizing enzymes comprising: 
 genetically engineering an enzyme to include a stabilizing amino acid substitution;    copolymerizing an amphiphile containing a salt selected from the group consisting of metal salts of iminodiacetic acid, nitrilotriacetic acid, and mixtures thereof with other polymerizable amphiphiles to form vesicles;    binding the genetically engineered enzyme to the salts on the outer surface of the vesicles.    
     
     
         4 . The method according to  claim 3  wherein the metal salts are selected from the group consisting of copper, nickel, cobalt, and zinc salts.  
     
     
         5 . The method according to  claim 3  wherein the stabilizing amino acid is selected from the group consisting to histidine or polyhistidine.  
     
     
         6 . The method according to  claim 3  wherein the enzyme is thioesterase.  
     
     
         7 . The method according to  claim 3  wherein the salt is a metal salt of iminodiacetic acid.  
     
     
         8 . The method according to  claim 3  wherein the salt is a metal salt of nitrilotriacetic acid.  
     
     
         9 . A method for stabilizing enzymes comparing: 
 genetically engineering an enzyme to include a stabilizing amino acid substitution;    attaching said stabilized enzyme to salt groups selected from the group consisting of metal salts of iminodiacetic acid, metal salts of nitrilotriacetic acid, and mixtures thereof on the surface of a particular inorganic carrier.    
     
     
         10 . The method according to  claim 9  wherein the metal salts are selected from the group consisting of copper, nickel, cobalt, and zinc salts.  
     
     
         11 . The method according to  claim 7  wherein the carrier is a metal oxide ceramic particles that can be formed in the Stober process starting with a metal alkoxide precursor.  
     
     
         12 . The method according to  claim 9  wherein the metal oxide particles are selected from the group consisting of silica, alumina, baria, titania, and gircinia.  
     
     
         13 . The method according to  claim 9  wherein the salt groups are metal salts of iminodiacetic acid.  
     
     
         14 . The method according to  claim 9  wherein the salt groups are metal salts of nitrilotriacetic acid.