ISSUES AND ADVANCES IN THE USE OF TRANSGENIC ORGANISMS FOR THE PRODUCTION OF THAUMATIN, THE INTENSELY SWEET PROTEIN FROM THAUMATOCOCCUS-DANIELLI

The thaumatins are a class of intensely sweet proteins isolated from t he fruit of the tropical plant Thaumatococcus danielli. Thaumatin is a pproved for use in many countries and has application as both a flavor enhancer and a high-intensity sweetener. The supply of naturally occu rring thaumatin is limited, which has prompted extensive research into its synthesis via transgenic organisms. The gene encoding thaumatin h as been introduced into various microorganisms under transcriptional c ontrol of heterologous promoters. Yields to date have been low, but th e factors governing more efficient microbial production have been iden tified. Continued research should allow microbial yields to be improve d to commercially viable levels. The unique properties of thaumatin as a food additive could well be exploited by the food industry. Alterna tively, the thaumatin gene could be engineered directly into selected fruit and vegetable crops to improve their flavor and sweetness.