It is well known that certain bacteria have developed resistance to the miracle antibiotic drugs when they were developed less than a century ago. Now scientists at McMaster University have found that resistance has been around for at least 30,000 years. Research findings show that antibiotic resistance is a natural phenomenon that predates modern clinical antibiotic use.
“Antibiotic resistance is seen as a current problem and the fact that antibiotics are becoming less effective because of resistance spreading in hospitals is a known fact,” said Gerry Wright, a professor at McMaster University and a principal investigator for the study recently published in Nature. “The big question is, where does all of this resistance come from?” After years of studying bacterial DNA extracted from soil frozen in 30,000-year-old permafrost from the Yukon Territories, the researchers were able to develop methods to isolate DNA. Using state-of-the-art molecular biological techniques, methods were developed to tease out small stretches of ancient DNA. Researchers discovered antibiotic resistant genes existed beside genes that encoded DNA for ancient life, such as mammoths, horse and bison as well as plants only found in that locality during the last interglacial period in the Pleistocene era. They focused on a specific area of antibiotic resistance to the drug vancomycin, a significant clinical problem that emerged in 1980s and continues to be associated with outbreaks of hospital-acquired infections worldwide. “We identified that these genes were present in the permafrost at depths consistent with the age of the other DNAs, such as the mammoth…these were not contemporary, but formed part of the same family tree. We then recreated the gene product in the lab, purified its protein, and showed that it had the same activity and structure then as it does now.” This is only the second time an ancient protein has been “revived” in a laboratory setting. Professor Wright said the breakthrough will have important impact on the understanding of antibiotic resistance. “Antibiotics are part of the natural ecology of the planet so when we think that we have developed some drug that won’t be susceptible to resistance or some new thing to use in medicine, we are completely kidding ourselves. These things are part of our natural world and therefore we need to be incredibly careful in how we use them. Microorganisms have figured out a way of how to get around them well before we even figured out how to use them.”
(Source: ScienceDaily, September 16, 2011)
