Effect of enzyme I of the bacterial phosphoenolpyruvate : sugar phosphotransferase system (PTS) on virulence in a murine model

Abstract

The phosphoenolpyruvate : sugar phosphotransferase system (PTS) catalyses translocation with concomitant phosphorylation of sugars and hexitols and it regulates metabolism in response to the availability of carbohydrates. The PTS forms an interface between energy and signal transduction and its inhibition is likely to have pleiotropic effects. It is present in about one-third of bacteria with fully sequenced genomes, including many common pathogens, but does not occur in eukaryotes. Enzyme I (ptsI) is the first component of the divergent protein phosphorylation cascade.ptsIdeletions were constructed inSalmonella typhimurium,Staphylococcus aureusandHaemophilus influenzaeand virulence of the mutants was characterized in an intraperitoneal mouse model. The log(attenuation) values were 2·3, 1·4 and 0·9 for theSal. typhimurium,Sta. aureusandH. influenzaeptsImutants, respectively. The degree of attenuation is correlated with the complexity of the respective PTS, which comprises approximately 40 components inSal. typhimurium, but only 5 inH. influenzae.