Tuberculosis led to the death of about 1.3 million people around the world in 2022 alone. From 2022 to 2023, there was a concerning 15 percent increase in tuberculosis cases in California. Tuberculosis is a bacterial infection caused by Mycobacterium tuberculosis, and it can be transmitted when a person who is sick with the disease coughs. But not everyone will show signs of illness when infected, and people can also develop latent tuberculosis infection (LTBI), which can turn into full blown tuberculosis at any time. These infections can also be difficult to treat, particularly as bacteria continue to evolve resistance to antibacterial drugs.
Researchers have now identified an enzymatic cocktail that can destroy several species of mycobacteria, including those that can cause tuberculosis. The findings have been reported in Microbiology Spectrum.
"Mycobacterial infections are particularly hard to treat due to poor efficacy with standard of care drugs that are used in multi-drug regimens resulting in significant toxicities and treatments lasting six months to years. This is often followed up by reemergence of the bacterial infection after a year of testing negative," said study co-author Jason Holder, PhD, Founder and Chief Science Officer at Endolytix Technology.
Holder noted that this cocktail is not related to small molecule antibiotics, or bacteriophages, which are viruses that only infect bacterial cells and have sometimes been used to treat challenging, drug-resistant bacterial infections.
In this study, the investigators created an enzymatic cocktail that takes aim at the envelope surrounding mycobacterial cells. The envelope is essential for the viability of mycobacteria, so when these specific enzymes destroy it, the bacteria are eliminated.
Once developed, the enzymes were tested in lab cell culture models. The drug was able to shred the envelope and kill both M. tuberculosis and nontuberculous mycobacteria (NTMs), which can both lead to fatal lung disease.
The investigators noted that the enzyme cocktail can be delivered to an infection with liposome capsules, and that this approach could lead to new treatments for lung diseases.
Study co-author Richard Slayden, PhD, a professor at Colorado State University, added that there do not seem to be many concerns about undesirable drug interactions with this cocktail, unlike many anti-mycobacterial drugs that are currently in use. These enzymes can be used in combination with standard antibiotic treatments as well so that lower concentrations of the drugs can be applied in a successful treatment. However, more tested will be needed before they can be brought to the clinic.
Sources: American Society for Microbiology, Microbiology Spectrum
