GLYCEROL MONOLAURATE INHIBITS THE PRODUCTION OF BETA-LACTAMASE, TOXICSHOCK SYNDROME TOXIN-1, AND OTHER STAPHYLOCOCCAL EXOPROTEINS BY INTERFERING WITH SIGNAL-TRANSDUCTION

Glycerol monolaurate (GML) is a naturally occurring surfactant that is used widely as an emulsifier in the food and cosmetics industries and is generally regarded as lacking in important biological activities. The recent observation that it inhibits the production of staphylococc al toxic shock toxin-1 (P. M. Schlievert, J. R. Deringer, M. H. Kim, S . J. Projan, and R. P. Novick, Antimicrob. Agents Chemother. 36:626-63 1, 1992) is therefore rather surprising and raises the interesting que stion of how such a compound might interact with cells. In this report , we show that GML inhibits the synthesis of most staphylococcal toxin s and other exoproteins and that it does so at the level of transcript ion. We find that GML blocks the induction but not the constitutive sy nthesis of p-lactamase, suggesting that it acts by interfering with si gnal transduction.