Replying to: W. Balemans et al. Nature 462, 10.1038/nature08667 (2009)Our studies led us to conclude that growth of major Gram-positive pathogens, including Staphylococcus aureus, is not inhibited by FASII-targeted antibiotics in septicaemic infection, owing to compensation by serum fatty acids. The comments of Balemans et al. challenge the generality of our results, mainly on the basis of their own work, which is aimed at developing FabI inhibitors for treatment of S. aureus infections. Their allusion to the documented use of FASII inhibitors to treat mycobacterial infections is misleading. Mycobacteria were not considered in our study, because (1) their main route of pathogenesis is not sepsis, and (2) they require mycolic acids for normal growth, which are lacking in serum. The results we present here further reinforce the conclusions of our article.