While sifting through the bacterial genome of salmonella, Cornell food scientists discovered mcr-9, a new, stealthy jumping gene so diabolical and robust that it resists one of the world’s few last-resort antibiotics.
Doctors deploy the antibiotic colistin when all other infection-fighting options are exhausted. But resistance to colistin has emerged around the globe, threatening its efficacy.
“This last-resort antibiotic has been designated a highest-priority antibiotic by the United Nations’ World Health Organization, and the mcr-9 gene causes bacteria to resist it,” said Martin Wiedmann, Cornell’s Gellert Family Professor in Food Safety and senior author on the study published May 7 in the journal Mbio. “In treatments, if colistin does not work, it literally could mean death for patients. If colistin resistance spreads, a lot of people will die.”
Co-lead author Laura Carroll, a computational biologist and Cornell doctoral candidate, found mcr-9 in the genome of a strain of foodborne pathogen salmonella.
Because the DNA sequence of the mcr-9 gene was similar to other genes that could cause bacteria to resist colistin, she suspected that the salmonella strain which carried mcr-9 was colistin-resistant. To her surprise, the salmonellastrain failed to show colistin resistance.
Knowing that the mcr-9 gene could jump to other bacteria or organisms, her colleague, senior research associate Ahmed Gaballa, a microbiologist and co-lead author, inserted the gene into a nonpathogenic strain of the bacterium E. coli. Gaballa was able to “turn on” mcr-9, making the E. coli strain resistant to colistin. That showed Carroll was initially correct.
“When we originally tested the salmonella isolate and found that it wasn’t resistant to colistin, we were perplexed,” Carroll said. “But when Ahmed cloned it into an E. coli host, he was able to find that the gene could confer resistance to colistin.”
Mcr-9 is the latest in this new series of “mobilized colistin-resistance” genes – originally discovered in 2015. The National Center for Biotechnology Information, part of the National Institutes of Health, has added details about this new gene to its database. Medical professionals and others can now use this information to identify mcr-9 in bacteria isolated from food products and people.
Details about mcr-9 in national and international databases enable scientists to develop better prevention and treatment, explained Wiedmann. “This improves our ability to get an early warning,” he said.
Bacteria isolated from food products can now be tested for mcr-9, and patients can be screened for colistin-resistant bacteria which possess mcr-9. “If you go to a hospital and this gene is floating around, that can be trouble. The gene is moveable. It jumps,” Wiedmann said.
“In a hospital setting, being able to screen a patient for resistance allows doctors and nurses to isolate the patient and maintain biosecurity.”
Wiedmann pointed out that while his lab is dedicated to food safety, the collaboration of scientists from different fields made the discovery possible. “In this age of complicated problems, we need the computational bioinformatics approach to find solutions,” he said. “Standard biological research and standard tests would not necessarily have found this gene.”
Carroll added: “It takes a village of a computational biologist, a microbiologist and a molecular biologist to make this sort of scientific discovery happen.”
Learn more: Cornell scientists discover new antibiotic resistance gene
The Latest on: Last-resort antibiotics
[google_news title=”” keyword=”last-resort antibiotics” num_posts=”10″ blurb_length=”0″ show_thumb=”left”]
via Google News
The Latest on: Last-resort antibiotics
- Patralekha Chatterjee | Amid row over masala, is the food we eat safe?on April 26, 2024 at 11:32 am
Amid all the talk about “Viksit Bharat” by 2047, it is worth remembering that a key difference between a developed and a developing country is in the quality of everyday life of ...
- Antibiotic-resistant hospital infections well above pre-COVID-19 levelson April 26, 2024 at 8:02 am
Two more findings: Hospital-acquired infections resistant to carbapenems — considered the antibiotics of last resort for severe infections — increased most. They remain at least 35% higher than ...
- Study: Antibiotic use in moderate COVID-19 linked to clinical deteriorationon April 26, 2024 at 7:56 am
Antibiotic treatment of adults hospitalized with moderate COVID-19 is associated with clinical deterioration, despite the drugs being given to over 40% of patients, according to new research being ...
- 8 UTI Home Remedies Other Than Antibioticson April 22, 2024 at 4:59 pm
While antibiotics are the most effective treatment for a UTI, you can use these home remedies to help manage your symptoms. Share on Pinterest A UTI can cause symptoms like bloody urine and pain ...
- Pandemic of drugs overuseon April 19, 2024 at 4:59 pm
For instance, European countries prescribe patients cheap penicillin-based antibiotics to treat pneumonia, whereas Nepali doctors prescribe expensive and last-resort antibiotics like Linezolid, ...
- Black women hospitalized in US with blood infection resistant to last-resort antibiotic at increased risk of deathon April 19, 2024 at 3:10 pm
New research being presented at this year's ESCIMD Global Congress (formerly ECCMID) in Barcelona, Spain (27–30 April), finds that the odds of death in Black women with a bloodstream infection (BSI) ...
- Black women hospitalised in USA with blood infection resistant to last-resort antibiotic at increased risk of deathon April 18, 2024 at 5:00 pm
Carbapenem-resistant Enterobacterales (CREs) are resistant to commonly prescribed antibiotics called carbapenems, which are considered the drugs of last resort for treating severe infections.
- Antibiotic-resistant ‘superbugs’ are being passed from pets to humanson April 13, 2024 at 6:42 am
Study finds pets in UK and Portugal carry and potentially transmit the same antibiotic-resistant bacteria as their owners.
- Bringing multidrug-resistant pathogens to their kneeson April 9, 2024 at 3:23 am
Nov. 5, 2020 — A research team discovers that by repurposing an antirheumatic gold drug, auranofin (AUR), 'last-resort' antibiotics can be resensitized for treatment of infections caused by ...
- Poultry giant Venky’s marketing antibiotics for growth promotion in farmson April 5, 2024 at 1:37 pm
In 2018, TBIJ revealed Venky’s was selling colistin as a growth promoter. Colistin is a “last resort” antibiotic owing to its importance in treating severe human infections. The revelations ...
via Bing News