ANALYSIS OF ICE NUCLEATION GENE PRODUCTS BY SITE-DIRECTED MUTAGENESIS

AN ICE NUCLEATION GENE FROM PSEUDOMONAS SYRINGAE IS CLONED IN E. COLI AND ANALYSED BY DIRECTED MUTAGENESIS. PRECISE DUPLICATIONS AND DELETIONS OF REPETITIVE DOMAINS ARE GENERATED; NON-REPETITIVE DOMAINS ARE TARGETED FOR PARTIAL DELETION. THE RESULTING CONSTRUCTS ARE ANALYSED FOR THEIR EFFECTS ON THE TEMPERATURE SPECTRUM OF NUCLEATION FREQUENCY AND FOR THE ABILITY OF THEIR GENE PRODUCTS TO BE INCORPORATED INTO INNER AND OUTER CELL MEMBRANES. THE RESULTS WILL PROVIDE INFORMATION ON THE ASSEMBLY AND FUNCTION OF ICE NUCLEI IN VIVO. THIS WILL MAKE POSSIBLE THEGENETIC ENGINEERING OF ICE NUCLEI FOR REDUCED VARIABILITY, WHICH WILL IMPROVE THEIR SUITABILITY FOR COMMERCIAL USE.