Aldol sensors for the rapid generation of tunable fluorescence by antibodycatalysis

The synthesis of novel fluorogenic retro-aldol substrates for aldolase anti body 38C2 is described. These substrates are efficiently and specifically p rocessed by antibody aldolases but not by natural cellular enzymes. Togethe r, the fluorogenic substrates and antibody aldolases provide reporter gene systems that are compatible with living cells. The broad scope of the antib ody aldolase allows for the processing of a range of substrates that can be designed to allow fluorescence monitoring at a variety of wavelengths. We also have developed the following concept in fluorescent protein tags. beta -Diketones bearing a fluorescent tag are bound Synthesis of the Aldol Senso rs covalently by the aldolase antibody and not other proteins. We anticipat e that proteins fused with the antibody can be tagged specifically and cova lently within living cells with fluorophores of virtually any color, thereb y providing an alternative to green fluorescent protein fusions.