Investigators working to stem the spread of antibiotic-resistant bacteria have taken a major step in their efforts to develop new treatments.
In mBio, researchers at The University of Texas Health Science Center at Houston (UTHealth) report they have identified a novel mechanism that a particular superbug uses to fend off a key front-line antibiotic called daptomycin. The superbug often affects critically ill patients.
This information is helping investigators identify compounds to knock out a mechanism of resistance in order to "disarm" the superbug.
Prior to the mass production of antibiotics, a cut or strep throat could lead to serious illness or even death. Antibiotics gave doctors the ability to treat bacterial infections. But, bacteria have developed mechanisms of resistance that can make antibiotics ineffective against the most aggressive superbugs.
Thousands of people succumb to superbug-related infections worldwide annually and superbugs account for $20 billion in excess health care costs in the United States each year.
"Antibiotic resistance is one of the major public health threats of the 21st Century," said Cesar Arias, M.D., Ph.D., the study's senior author and associate professor in the Division of Infectious Diseases at the UTHealth Medical School. "These superbugs can make antibiotics useless, which makes certain bacterial infections virtually untreatable."
While there are several types of antibiotic-resistant bacteria, the study focused on a hard-to-treat superbug called vancomycin-resistant enterococci or VRE. VRE usually affect patients who have a compromised immune system or who are critically ill.
The frequency of VRE recovered from hospitalized patients in the United States has increased eightfold in the last 15 years, becoming the second most common hospital-associated bacterium in the United States, Arias said.
The superbug appears to be building resistance to one of the few antibiotics that works against it - daptomycin.
To see how VRE developed the ability to ward off daptomycin during the course of treatment, Arias' team used fluorescent labeled daptomycin and observed the interaction between the superbug and the antibiotic with the aid of advanced microscopy techniques.