Researchers are looking 59 million years into the past for a solution to the problem of antibiotic resistance, reports New Scientist's Wendy Zukerman. The antimicrobial agent that researchers are now experimenting with was last seen on Earth when the planet was recovering from the mass extinction that wiped out the dinosaurs, Zukerman says. It is, apparently, still strong enough to destroy some modern pathogens that have seemed invincible. The research started last year when the Infectious Diseases Society of America began a program to produce 10 antibiotics by 2020 powerful enough to act against multidrug-resistant microbes. Some promising molecules have been found in the tissues of lampreys, Zukerman says, but recent research has led scientists to the wallaby. Researchers "scoured the wallaby genome and found genes that code for 14 cathelicidin peptides, a component of the innate immune system. Lab tests revealed that many of the peptides could kill a range of multidrug-resistant pathogens — without damaging human cells," Zukerman says. "The team noticed that genes in five of the cathelicidins were remarkably similar and probably evolved from a single ancestor." The researchers then worked backwards to find the genetic sequence of the original peptide — active 59 million years ago — and produced a synthetic version, effectively "resurrecting" the ancient peptide, she adds. In lab tests, it destroyed six out of seven multidrug-resistant bugs and was 10 to 30 times stronger than modern antibiotics.
Sep 29, 2011