Natural Antibiotic from Sweat can Fight TB Germs, Bugs: Study

Scientists have discovered a natural antibiotic from human sweat that can fight tuberculosis germs and other bugs.

Dermcidin is an anti-microbial (antibiotic) peptide (AMP) produced by human sweat glands. The antibiotic agent is effective in killing germs when skin is injured by a cut or bug bite.

There are 1,700 types of natural antibiotics, but until now it was not known how these substances work. Researchers from the University of Edinburgh, U.K., have uncovered the atomic structure of dermcidin in order to find out what makes the compound an effective weapon to fight off bugs.

Natural substances like dermcidin are more effective in the long term than traditional antibiotics, as germs do not have the ability to quickly develop resistance against them. It is known that dermcidin is produced in salty, slightly acidic sweat. "The molecule then forms tiny channels perforating the cell membrane of bugs, which are stabilized by charged particles of zinc present in sweat. As a result, water charged particles flow across the membrane, ultimately killing the microbes," the researchers said.  

When they uncovered the atomic structure of the compound, they found that the molecular channel is unusually long, permeable and adaptable, representing a new class of membrane protein. The research team also found that dermcidin can adapt to variable types of membrane to kill off bacteria and fungi at the same time. The substance is effective against many pathogens such as tuberculosis, Mycobacterium tuberculosis, or Staphylococcus aureus.

Researchers believe the findings could contribute to the development of new antibiotics that have the ability to attack multi-resistant bacteria. 

"Antibiotics are not only available on prescription. Our own bodies produce efficient substances to fend off bacteria, fungi and viruses. Now that we know in detail how these natural antibiotics work, we can use this to help develop infection-fighting drugs that are more effective than conventional antibiotics," Dr. Ulrich Zachariae, of the University of Edinburgh's School of Physics, said in a statement.

The findings of the study are published in the journal Proceedings of the National Academy of Sciences.