[New targets in the field of antibacterial agents. Prospective aspects]

Even though a great number of antibiotics and antiseptic agents are available at present, these substances are often rendered ineffective by the capacity of bacteria to develop resistance to them. The importance of continuing research in this area cannot be sufficiently stressed. Of the various strategies likely to yield innovative products in the future, two can be applied not only to the search for new antibiotics, but also for finding new antiseptics. Numerous Gram-negative, as well as some Gram-positive, bacteria have efflux systems by which they excrete toxic substances, in particular, antibiotics. Because bacterial efflux pumps differ from those in eukaryotic cells, it should be possible to find inhibitors that are specific for the bacterial pumps. The colonization of biological supports by bacteria leads to the development of biofilms, which are highly resistant to both antiseptics and antibiotics. Bacteria that grow and persist within the biofilm differ metabolically from bacteria growing freely in culture. The study of the various steps in the colonization of supports might provide clues to the discovery of products that could penetrate the exopolysaccharide layer which forms the biofilm and that would be active against bacteria in this particular metabolic state.