Effectiveness of Antibiotics Boosted by Newly Created Compounds

Medical scientists have developed a method of boosting the effectiveness of antibiotics that may prove useful in combating deadly bacterial diseases such as anthrax or MRSA.

By using inhibitor compounds that block an enzyme called neuronal nitric oxide synthase (NOS), researchers Thomas Poulos of University of California - Irvine and Richard Silverman of Northwestern University, demonstrated in an earlier study the ability to treat neurodegenerative diseases by "blocking overproduction of cell-killing nitric oxide within neurons."

Now, it turns out, the method could have other applications, notably by increasing an antibiotic's effectiveness by pairing them with NOS-blocking inhibitor compounds.

"We found that NOS inhibitors were extremely successful at inhibiting neurodegeneration in an animal model, and if they could be successful combating other diseases, we wanted to identify that as quickly as possible to help other people," said Poulos, who is also a professor of biochemistry, chemistry and pharmaceutical sciences at UC Irvine.

Poulos and Silverman preformed tests of their compounds on Bacillus subtilis, nonpathogenic bacteria very similar to Staphylococcus aureus (known as MRSA), and Bacillus anthracis, which causes anthrax.

In treatment that included a NOS inhibitor compound and antibiotic, bacteria were killed more effectively than in treatments with antibiotics alone.

Further testing concluded that the increased efficacy comes from the way the compounds bond together.

"Now that we know which region of the NOS to target, we should to be able to develop compounds that selectively bind to bacterial NOS," Poulos said, adding that his team will also need to try out those compounds in animal models.

The research is published in the Proceedings of the National Academy of Sciences.