Image: Color-enhanced scanning electron micrograph showing Salmonella Typhimurium (red) invading cultured human cells. Image: Rocky Mountain Laboratories, NIAID, NIH
The genes of this plasmid modify several features of the pathogenic bacterium, and so could be likely targets to slow or halt the infection’s soaring resistance to antibiotics.
Antibiotic resistance was recently declared ‘one of the greatest threats to human health today’ by the WHO, and experts fear the time is fast approaching when some everyday infections will be untreatable, making routine procedures such as hip replacements much more risky. Not only have some common infections or illnesses become resistant to the antibiotics usually used to treat them, a really pressing medical problem now is the rapid rise of ‘superbugs’ or multidrug-resistant bacteria, which are immune to almost all of the antibiotics that are currently available. This means that some clinical procedures like organ transplants, chemotherapy or the care of premature infants could become too dangerous to carry out, as hospitals become hotbeds for highly resistant pathogens. Effectively, this could spell ‘the end of modern medicine’, in the words of the WHO.
“We’ve come to a point where we need to find ways of reversing the resistance of bacteria to antibiotics, as more and more of our drugs are rendered useless against some of the most common and threatening infections and diseases,” says Antonio. “Within IBEC alone, we have teams working on several different ways to overcome bacterial resistance: either developing new drugs against new targets, or interfering with those plasmids which confer resistance against the existing antibiotics that are available. These are both strategies that could help to overcome bacterial resistance to antibiotics, but they both take time.”
IBEC’s Bacterial Infections: Antimicrobial Therapies group, led by Eduard Torrents, explores the use of different bioengineering approaches to reveal ways to eradicate multi-drug resistant bacteria. Eduard’s group follows a strategy that is complementary to that of Antonio: instead of trying to deal with the plasmids that are triggering the resistance to today’s antibiotics, as Antonio does, they are trying to develop brand new drugs against new targets. They’re also using nanotechnological approaches for antibiotic delivery, to improve therapeutic efficiency and minimize unwanted side effects. As Eduard explains, “The emergence and increasing prevalence of bacterial strains that are resistant to available antibiotics demand the discovery of new therapeutic approaches.”
Other researchers at IBEC are also involved in the fight against antibiotic resistance. TheraEDGE, a European-funded project involving IBEC Director Josep Samitier’s Nanobioengineering group, is aimed at finding solutions for the early diagnosis and effective treatment of respiratory tract infections, by eliminating diagnostic uncertainties and recommending the correct course of treatment. In this way, the project aims to help reduce the growth of antibiotic resistance in diseases such as bronchitis or pneumonia.
Reference article: Paytubi S, Aznar S, Madrid C, Balsalobre C, Dillon SC, Dorman CJ, Juárez A. (2013). “A novel role for antibiotic resistance plasmids in facilitating Salmonella adaptation to non-host environments.” Environ Microbiol., 2013 Aug 19. doi: 10.1111/1462-2920.12244