Beating Bacteria without Antibiotics

Dr. Daniel Nelson from the Department of Veterinary Medicine and Institute of Bioscience & Biotechnology Research is nominated for UMD Invention of the Year.

Image Credit: Edwin Remsberg

April 14, 2015 Sara Gavin

When a person becomes infected with Methicillin Resistant Staphylococcus aureus– better known as MRSA – treatment options are severely limited due to the fact that nearly all antibiotics are rendered useless against the dangerous bacteria. However, Dr. Daniel Nelson, an associate professor in the Department of Veterinary Medicine and at the Institute for Bioscience and Biotechnology Research (IBBR) in Rockville, has discovered an enzyme that can attack and destroy MRSA by chewing through the bacteria’s cell wall. Nelson’s patented enzyme has earned him a spot as one of nine nominees for the University of Maryland’s Invention of the Year.

The enzyme, named PlyGRCS, is produced by bacteriophage – viruses that infect bacteria. Nelson has been studying these specific types of enzymes, also called endolysins, for more than a decade. Because the enzymes function like antibiotics, Nelson coined the term “enzybiotic” in 2001 – a term now widely used in the scientific community.

The enzymes work by adhering to the surface of the bacteria’s cell wall and then chewing through the wall, causing the cell to explode and die. To date, Nelson has identified and studied more than a dozen enzymes that are effective for eliminating a number of bacterium including those that cause staph infections, pneumonia, strep throat, anthrax, as well as animal diseases like bovine mastitis.

What makes PlyGRCS stand out, however, is the fact that it cleaves through the cell wall in two dimensions, opposed to all other enzymes that only attack the cell in one place.

 “Our enzyme is the first one that can cut two different bonds in the structure of the cell wall and because of that, it’s highly active,” says Nelson. “Think of it like girders of a building. We’re cutting the girders in two dimensions. You have to make a lot less cuts to make the building fall.”

As concerns over antibiotic resistance continue to grow, alternative therapeutic approaches – like enzybiotics – will become more important, says Nelson, who holds PhDs in Biochemistry and Molecular Biology as well as an MBA in Entrepreneurship.

While the enzymes are currently not approved for human treatment in the United States, Nelson says they could one day be administered via throat sprays, lozenges, nasal inhalers, skin creams and even chewing gums, depending on the type of bacterial infection. Animals could be treated through feed mixtures or teat dips and the enzymes could also be incorporated into disinfectant sprays or foggers to treat surfaces and facilities where harmful bacteria is present.

“Not many people have heard of these enzymes but I think there will be a lot more people hearing about them soon,” says Nelson.

UMD will honor Nelson and the other eight nominees for their promising inventions at the Celebration of Innovation and Partnerships event on April 29th, held as part of the university’s “30 Days of EnTERPreneurship,” a month-long celebration and exhibition of innovation and entrepreneurship. The nine nominees were selected based upon their invention’s potential impact on science, society, and the open market. Winners will be announced in three categories: physical sciences, information sciences and life sciences, for which Nelson is nominated.