Researchers create molecular drills to destroy superbugs

One of the biggest challenges in modern medicine is devising new antibiotics that can kill so-called superbugs that have developed resistance to nearly all antibiotics. Scientists have created a new method of killing these superbugs known as a molecular drill. In some cases, these molecular drills can make antibiotics effective again.

Scientists have shown that motorized molecules developed at Rice are effective at killing antibiotic-resistant microbes within minutes. The bacteria that the molecular drills are effective against are estimated to kill as many as 10 million people yearly by 2050 and don't respond to any treatments.

The tiny motors the team created target the bacteria and once activated with light, burrow through the exterior layers of the of the bacteria. The antibiotics that the bacteria are resistant to become effective again once they get through the openings made by the drill.

The molecular drills are paddlelike molecules that can be prompted to spin at 3 million rotations per second when activated with light. In testing, the molecules proved effective at killing Klebsiella pneumoniae within minutes. Scientists say that the bacteria has no way to defend against the molecular drills because it's a mechanical action, not a chemical effect.

The team says that the motors increase the susceptibility of K. pneumonia to meropenem, an antibacterial drug that the bacteria had developed a resistance to. Using the new technique, the drug can get through the cell wall. The team says that it breathes new life into previously ineffective antibiotics. In bacterial colonies targeted with a small concentration of nanomachines alone killed up to 17% of the cells. That percentage increased to 65% with the addition of meropenem. After balancing the motors and antibiotics, the team was able to kill 94% of the bacteria.