Researchers from the National Autonomous University of Mexico (UNAM) have identified new ways to combat tuberculosis and reduce bacterial resistance, developing three new antibiotics derived from scorpion venom and habanero peppers.

A team led by Lourival Domingos Possani Postay, from the Institute of Biotechnology's Morelos campus, created two drugs that demonstrated efficacy against the bacterium Mycobacterium tuberculosis, responsible for tuberculosis, as well as against Staphylococcus aureus, a microorganism that in hospital environments can cause various clinical complications, from skin infections to potentially fatal diseases such as pneumonia, meningitis, septicemia, and endocarditis.

The antibiotics were derived from the venom of the scorpion Diplocentrus melici, native to the state of Veracruz. The team was able to isolate two colorless molecules called benzoquinones—heterocyclic compounds that do not contain amino acids—from the arachnid's toxin.

These molecules have a particular property: When they come into contact with air, they oxidize and change color. One becomes blue and the other red. This behavior allowed scientists to determine their chemical structure, synthesize them in the laboratory, and evaluate their biological properties.

The results showed that the blue benzoquinone has the capacity to act against the bacteria that cause tuberculosis, while the red one is effective against Staphylococcus aureus. Richard Zare, a renowned expert in the field of physical chemistry and a professor of chemistry at Stanford University, participated in this process, which strengthened the validation of the findings.

The project also involved the collaboration of Rogelio Hernández Pando, from the Salvador Zubirán National Institute of Medical Sciences and Nutrition, who evaluated the effect of blue benzoquinone in a mouse model with induced tuberculosis. After the trials, he concluded that the molecule works as a highly effective antibiotic against this disease.

Subsequently, the team conducted further tests and found that the same substance is also capable of eliminating other bacteria, such as Acinetobacter baumannii, a highly resistant opportunistic pathogen that is often associated with infections in the blood, urinary tract, lungs, and wounds, especially in hospitals.

The molecules obtained from the scorpion venom have already been patented in Mexico and South Africa. Currently, researchers are working on the development of nanoparticles that function as stabilizers and protection systems, so that antibiotics can be administered safely in the body.

According to Possani Postay, the next step is to carry out clinical trials, although he recognizes that these involve considerable investment. For this reason, he expressed interest in collaborating with a national pharmaceutical company to bring the compounds to large-scale production.

From a Sauce to an Antibiotic

At the same time, another group from the UNAM Biotechnology Institute identified a peptide in the habanero chili bell pepper that has the capacity to fight opportunistic bacteria that can cause serious infections, particularly in patients with weakened immune systems.

This project, led by Gerardo Corzo Burguete together with Georgina Estrada Tapia from the Yucatan Scientific Research Center, focused on the bacterium Pseudomonas aeruginosa, considered by the World Health Organization as a high-priority pathogen due to its resistance to conventional antibiotics.

The scientists identified a peptide called defensin J1-1 in the habanero bell pepper (Capsicum chinense). Based on this finding, they developed a biotechnological process to produce a drug called XisHar J1-1, which proved effective against Pseudomonas aeruginosa and has the potential to treat infections caused by fungi.

The procedure involved the genetic modification of a bacterium to induce the production of J1-1 defensin. Subsequently, the modified microorganism was cultured by submerged fermentation, an industrial technique that allows the generation of compounds on a large scale. Finally, the peptide was extracted and purified for use as an antibiotic.

Although the experimental results were positive, Estrada Tapia pointed out that the study has limitations, since it did not use a resistant strain from patients, but a laboratory strain. However, she indicated that both defensin and its synthetic variants showed efficacy and already have a patent in Mexico.

The team stressed the need for further research, since these molecules can be degraded in different organisms. Even so, they are confident that the next phase, which includes tests against resistant strains isolated from patients, will allow them to validate their therapeutic potential.

Iván Arenas Sosa, a member of the group, emphasized that although there is still a long way to go, the advances represent a promising method of combating antimicrobial resistance, considered one of the main threats to global health.

"The problem of antibiotic-resistant bacteria has increased in recent years and will continue in the future. Therefore, it is essential to promote projects aimed at the discovery of new molecules and the development of innovative treatments to address antimicrobial resistance," he concluded.

This story first appeared on WIRED en Español and has been translated from Spanish.