Intein-modified enzymes, their production and industrial applications

1. A method of making an intein modified protein including:

identifying a plurality of cysteine, serine or threonine sites within the protein, whether native or introduced;

analyzing the local sequence of each cysteine, serine or threonine site in the plurality of cysteine, serine or threonine sites with a support vector machine;

identifying an active site of the protein, wherein a respective distance separates the active site and each of the cysteine, serine or threonine sites in the plurality of cysteine, serine or threonine sites, and identifying the respective distance between the active site and each of the cysteine, serine or threonine sites in the plurality of cysteine, serine or threonine sites; and

identifying a secondary structure of the protein at each of the cysteine, serine or threonine sites in the plurality of cysteine, serine or threonine sites;

inserting an intein into the protein at a site immediately before one of the cysteine, serine or threonine sites in the plurality of cysteine, serine or threonine sites that is ranked 0.75 or higher by the support vector machine, within ten angstroms of the active site, and within ten amino acids from a loop-β-sheet junction or within ten amino acids from a loop-α-helix junction; and

screening the intein modified protein to determine if the intein modified protein has a permissive or switching phenotype.

2. The method of claim 1 further comprising selecting the intein modified protein if it has a switching phenotype and switching is inducible upon exposure to an induction condition.

3. The method of claim 2 , wherein the induction condition is the intein modified protein having an induction temperature of 50° C. or greater.