Hiroyoshi Matsumura, Professor of College of Life Sciences at Ritsumeikan University, teamed with Junso Fujita, a third year Ph. D. student of Graduate School of Engineering at Osaka University, Daniel S. Pilch, Associate Professor at Rutgers University and other researchers, developed a drug effective against methicillin-resistant Staphylococcus aureus (MRSA), a strain of bacteria that developed resistance to antibiotics. The findings have been recently published on ACS Chemical Biology, an online comprehensive scientific journal.

MRSA is a strain of bacterium that has developed resistance to antibiotic drugs because of antibiotics overuse. Due to this characteristic, treatment of MRSA infection relies on immune systems of patients. Therefore, the infection is known to become especially severe when a patient with a weakened immune system is affected.

Previously, the research group developed a new therapeutic drug against MRSA infection that binds Filamentous temperature-sensitive protein Z (FtsZ), a cell division protein in MRSA. When the drug binds FtsZ, its function is weakened, resulting in inhibiting MRSA proliferation. If MRSA cannot proliferate, it is killed. Experiments conducted on mice showed that the drug was highly effective, but when used continually, MRSA developed resistance on it as well.

Given this situation, this research developed a second drug that can treat MRSA that developed resistance to the first drug. In addition, the research explained why the first drug became ineffective and the second drug became effective, and identified “structural flexibility of the drug” as the key factor.

Since the research revealed the process of resistance development in MRSA as well as its countermeasures, development of more drugs effective against MRSA infection can be expected.

The research was jointly conducted by Ritsumeikan University, Osaka University, and Rutgers University.