Microbial Genomics<\/a>, uncovered how the bacterium evolved and adapted quietly for decades, accumulating small changes that eventually made it resistant to antibiotics.<\/p>\nLead researcher Benjamin Evans said: “We know that bacteria that cause infections in people can adapt to the antibiotics we use to treat them, rendering the antibiotics ineffective.<\/p>\n
“We looked at a specific type of bacterium called Acinetobacter baumannii from the 1970s to the present day.<\/p>\n
![\"mufid-majnun-J12RfFH-2ZE-unsplash\"](\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAQAAAADCAQAAAAe\/WZNAAAAEElEQVR42mM8U88ABowYDABAxQPltt5zqAAAAABJRU5ErkJggg==\")
<\/p>\n
Mufid Majnun<\/p>\n
“This bacterium particularly thrives in hospital environments and can cause infections that are extremely difficult to treat – particularly for vulnerable patients.<\/p>\n
“Understanding how it evolved into such a formidable threat is really important in stopping its spread. But until now, the genetic events behind this bacterium’s success were poorly understood.<\/p>\n
“What we found is that it has adapted in waves, with each wave producing bacteria that were better adapted to resist antibiotics than the previous wave.<\/p>\n
“Our work provides one of the clearest pictures yet of how antibiotic resistance can accumulate gradually – and then suddenly tip the balance in favor of the pathogen.<\/p>\n
“One thing is clear – this superbug didn’t just appear. It was decades in the making, and it’s still evolving.”<\/p>\n
Scientists made the breakthrough by combining decades-old bacterial samples with cutting-edge genome sequencing.<\/p>\n
The team assembled a unique collection of 226 Acinetobacter baumannii samples dating from the 1970s to the early 2000s.<\/p>\n
The historical samples were carefully grown in the lab before their DNA was extracted, purified and sequenced.<\/p>\n
To build a global picture, the newly sequenced genomes were merged with more than 1,000 more recent genomes from six continents around the world.<\/p>\n
Using high-performance computing, the scientists compared all 1,281 chromosomes and created a detailed evolutionary tree.<\/p>\n
They paired this analysis with a comprehensive scan of antimicrobial resistance genes, tracking how these genes appeared, disappeared and reshaped the bacteria over time.<\/p>\n
<\/p>\n
Aconitum<\/p>\n
By Talker<\/p>\n
By aligning genetic changes with sample dates and locations, the researchers identified when key resistance traits emerged and how they spread globally.<\/p>\n
The combination of historical and modern approaches allowed the researchers to reconstruct the pathogen’s evolution over decades, revealing how it became a dominant, drug-resistant threat.<\/p>\n
Evans, from UEA’s Norwich Medical School, said: “Comparing patterns in the DNA sequence in the genomes allowed us to see how this bacteria has evolved over time, and how it has become more resistant to antibiotics.<\/p>\n
“We found that it didn’t suddenly emerge as a superbug.<\/p>\n
“Instead, it crept into dominance – and by around 2005, it had become the leading lineage of A. baumannii worldwide.”<\/p>\n
But he explained that what happened around that time is key.<\/p>\n
The researchers identified the acquisition of two major genetic elements \u2014 including a gene called oxa23, known for conferring resistance to powerful antibiotics \u2014 as a “turning point”.<\/p>\n
That effectively “supercharged” the bacterium’s ability to survive treatment. It became much harder to kill.<\/p>\n
The team also found that the bacterium in question isn’t a single uniform strain.<\/p>\n
Instead, it can be divided into at least four distinct groups, each following its own evolutionary path.<\/p>\n
Three of the groups appear to show a gradual, step-by-step evolution over time \u2014 like a slow genetic arms race against modern medicine.<\/p>\n
But a fourth group stands apart.<\/p>\n
<\/p>\n
National Institute of Allergy and Infectious Diseases<\/p>\n
By Talker<\/p>\n
Evans said: “This ‘group 4’ lineage appears to have branched off independently and is now being detected more frequently in recent samples.<\/p>\n
“This is worrying because it means that a newer and potentially better adapted variant may already be on the rise.”<\/p>\n
He added: “This work is really important because understanding how antibiotic-resistant bacteria respond to changes in antibiotic use over time is essential for guiding policies on how we use antibiotics now and in the future.<\/p>\n
“This is particularly important for bacteria like Acinetobacter baumannii.<\/p>\n
“These bacteria represent a serious threat to healthcare systems worldwide, and we need new approaches to combat them otherwise infections will become untreatable.”<\/p>\n
The research was supported with funding from the Biotechnology and Biological Sciences Research Council<\/a> (BBSRC).<\/p>\nSadhana Sharma, UKRI-Biotechnology and Biological Sciences Anti-Microbial Resistance lead, said: “This study shows how a major hospital superbug evolved over decades, quietly adapting into distinct, drug-resistant groups and spreading globally.<\/p>\n
“It underlines how antimicrobial resistance builds over time, and why understanding these changes is critical to staying ahead.”<\/p>\n
Sharma added: “It also highlights the importance of international collaboration, and sustained BBSRC investment in fundamental bioscience to protect health, advance knowledge, improve lives and drive growth.”<\/p>\n","protected":false},"excerpt":{"rendered":"CDC By Talker By Stephen Beech Hospital samples from the 1970s helped reveal how a deadly antibiotic-resistant “superbug”…\n","protected":false},"author":2,"featured_media":776223,"comment_status":"","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[7],"tags":[275265,275264,2719,29815,4345,13929,13934,13927,4468,13931,49,48,7820,316,2775,13930,15020,2724,10129,32674,13928,66,23441,51048],"class_list":["post-776222","post","type-post","status-publish","format-standard","has-post-thumbnail","category-science","tag-acinetobacter","tag-acinetobacter-baumannii","tag-antibiotic","tag-antimicrobial-resistance","tag-bacteria","tag-biochemistry","tag-biological-evolution","tag-biology","tag-biotechnology","tag-branches-of-genetics","tag-ca","tag-canada","tag-evolution","tag-genetics","tag-genome","tag-health-sciences","tag-infection","tag-infectious-diseases","tag-life-sciences","tag-microbiology","tag-molecular-biology","tag-science","tag-stephen-beech","tag-whole-genome-sequencing"],"_links":{"self":[{"href":"https:\/\/www.newsbeep.com\/ca\/wp-json\/wp\/v2\/posts\/776222","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.newsbeep.com\/ca\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.newsbeep.com\/ca\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/ca\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/ca\/wp-json\/wp\/v2\/comments?post=776222"}],"version-history":[{"count":0,"href":"https:\/\/www.newsbeep.com\/ca\/wp-json\/wp\/v2\/posts\/776222\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/ca\/wp-json\/wp\/v2\/media\/776223"}],"wp:attachment":[{"href":"https:\/\/www.newsbeep.com\/ca\/wp-json\/wp\/v2\/media?parent=776222"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.newsbeep.com\/ca\/wp-json\/wp\/v2\/categories?post=776222"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.newsbeep.com\/ca\/wp-json\/wp\/v2\/tags?post=776222"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}