Scientists this week announced the discovery of a new class of antibiotic, developed through a novel approach from naturally occurring microbes, which shows promise for fighting disease without leading to development of resistant pathogens.

The new type of antibiotic, called teixobactin, kills a wide range of pathogens including methicillin-resistant Staphylococcus aureus (MRSA) according to news reports.

Most existing antibiotics are derived from natural sources such as various types of fungi. Scientists culture the microbes in laboratories to produce the antibiotic. However, the researchers on this project note, 99 percent of these naturally occurring microbes cannot be grown effectively in a laboratory environment, leaving a huge, untapped resource of potential antibiotic-producing organisms.

For this study, reported in the January 7 issue of the journal Nature, the researchers developed several methods to grow uncultured organisms by cultivation in situ or by using specific growth factors. They discovered teixobactin, through screeing of those uncultured bacteria. According to the researchers, teixobactin inhibits cell wall synthesis by binding to a highly conserved motif of lipid II (precursor of peptidoglycan) and lipid III (precursor of cell wall teichoic acid). In their tests, they did not obtain any mutants of Staphylococcus aureus or Mycobacterium tuberculosis resistant to teixobactin. They add that the properties of this compound suggest a path towards developing antibiotics that are likely to avoid development of resistance.

Quoted in a Wall Street Journal article, one of the lead researchers, Kim Lewis, PhD, from Northeastern University in Boston, says clinical trials could begin in about two years, and likely would take two to three years to complete.