At a time when multi-drug resistant bacteria are proliferating, antibiotic development by big pharma has taken a steep decline during the 90s and 2000s for a number of reasons. To address this regulatory and economic incentives have been put in place to encourage big pharma to once again invest in antibiotics. It has been predicted that if the problem of multi-drug resistant bacteria is not addressed immediately they will potentially cause the death of 300 million people during the next 35 years . This is the antibiotic crisis.
Awareness is growing and there have been some very encouraging recent developments which should allow small scale biotech to take centre stage in antibiotic discovery. It may sound surprising but it is nonetheless true (and encouraging) that 99% of bacteria in the natural environment are uncultured . New simple techniques have been developed that allow many of these “unculturable” bacteria to be grown.
A technology called the iChip facilitates high-throughput culture of soil samples. It was used in the discovery of a new species of ß-proteobacteria provisionally named Eleftheria terrae. E. terrae secretes an antibiotic called teixobactin which is effective against gram positive (no outer membrane) pathogens such as Staphylococcus aureus and Mycobacterium tuberculosis.
Teixobactin inhibits the synthesis of peptidoglycan which is gram positive bacteria’s main defense against environmental factors. In addition inhibiting peptidoglycan synthesis leads to the buildup of toxic intermediates that lyse gram positive bacteria .
There are many more antibiotics to be found in the soil.
- Bettiol, Esther, and Stephan Harbarth. ‘Development of New Antibiotics: Taking off Finally’. Swiss Med Wkly 145 (2015): w14167. http://www.smw.ch/content/smw-2015-14167/.
- Ling, Losee L., Tanja Schneider, Aaron J. Peoples, Amy L. Spoering, Ina Engels, Brian P. Conlon, Anna Mueller, et al. ‘A New Antibiotic Kills Pathogens without Detectable Resistance’. Nature 517, no. 7535 (7 January 2015): 455–59. doi:10.1038/nature14098.