2 New Promising Antibiotics Found in Human Microbiome

Researchers at The Rockefeller University have identified two new promising antibiotics produced by bacteria residing inside the human body.

The newly discovered antibiotics, described in a paper published in the journal Nature Chemical Biology, are found in a family of bacteria called Rhodococcus. Dubbed as humimycin A and humimycin B, the two antibiotics proved especially effective against Staphylococcus and Streptococcus bacteria.

To identify the new antibiotics, the researchers first developed a specialized computer software identify genes in a microbe's genome that were likely to produce molecules known as non-ribosomal peptides that form the basis of many antibiotics. By using computational methods, the researchers were able to study natural molecules produced by bacteria that is normally can't be grown in laboratory.

According to a press release, their specialized computational software identified 57 potentially useful gene clusters. Out of those, the researchers chose 30 of the clusters. Using a method called solid-phase peptide synthesis, the researchers were able to manufacture 25 different compounds. They then tested these compounds against human pathogens.

The researchers successfully identified two closely related antibiotics that proved to be effective against Staphylococcus and Streptococcus bacteria, which can cause dangerous infections in humans and tend to grow resistant to various antibiotics.

Experimenting with the newly discovered antibiotics, the researchers noted that the humimycins work by inhibiting an enzyme that bacteria use to build their cell walls. The cell walls of the bacteria play a crucial role in their survivability. When the cell wall building pathway is interrupted, the bacteria die.

With their findings, the researchers hope to ignite the search of molecules produced by the genomes of bacteria living inside the human body to find potentially useful antibiotics.

The rise of more powerful antibiotic-resistant bacteria has made scientists and researchers scramble for stronger weapon against the pathogens. In the United States alone, at least two million people are infected with antibiotic-resistant bacteria and at least 23,000 die every years as a direct result of the bacterial infection.