Molecule from ticks may aid antibiotics

A molecule derived from ticks may enhance antibiotic-based treatments of methicillin-resistant Staphylococcus aureus (MRSA) infections, a Yale-led study reports. MRSA causes thousands of U.S. deaths per year, and when the bacteria form aggregates called biofilms, which shield them both from antibiotics and the immune system, they are especially resilient.

Erol Fikrig, M.D., Waldemar Von Zedtwitz Professor of Medicine (Infectious Diseases) and professor of epidemiology (microbial diseases) and of microbial pathogenesis, and colleagues had previously found that the tick-derived molecule, the glycoprotein IAGFP, prevented MRSA from forming biofilms, as did an IAGFP-derived protein, P1. Yet on their own, these tick-derived molecules did not kill bacteria.

Fikrig and his team reported in Antimicrobial Agents and Chemotherapy, published on April 24, that IAGFP and P1 enhanced the ability of three different antibiotics to kill MRSA in bacterial culture. Further, in a potential clinical application, adding a layer of P1 to antibiotic-treated catheters reduced MRSA’s ability to attach to them, making P1 “a potential prophylactic coating for catheters and other indwelling devices,” according to first author Nabil M. Abraham, Ph.D., who was a postdoctoral fellow in Fikrig’s lab.