Research Round-Up

Antimicrobial resistance outlook Research round-up

Highlights from research. By Elizabeth Svoboda

Vaccination curbs resistance High vaccination rates can help to limit needless drug use that drives antibiotic resistance, say researchers from Johns Hopkins University in Baltimore, Maryland. In an analysis of prescriptions in the United States, the team found that higher rates of influenza vaccination correlated with less use of antibiotics. Epidemiologist Eili Klein and his team combed large databases of antibiotic

prescriptions written from CROPPED) 3.0, BY-NC-ND LAB COLLINS / MIT (CC 2010 to 2017, as well as records Bacteria did not develop resistance to an antibiotic called halicin (L) , but they did to another drug (R). of state vaccination rates over the same period from the US commonly arise with flu. The for microbes that churn out of drug-resistant bacterial Centers for Disease Control researchers think that tackling bacteria-killing compounds. strains, such as Mycobacterium and Prevention. They used a a hesitancy to vaccinate With returns on this strategy tuberculosis and Clostridioides regression analysis to find the could therefore help to keep now mostly non-existent, the difficile, it came through with relationship between the two antimicrobial resistance at bay. MIT researchers decided to put flying colours, swiftly killing the data sets. a fresh spin on the discovery strains. After controlling for Open Forum Infect. Dis. 7, process. Computer scientist In a broader scan of more socio-economic factors and ofaa223 (2020) Regina Barzilay and her team than 100 million known differences in health-care trained a neural network molecules, the MIT system access, the researchers found to recognize the molecular identified another eight that for every 10-percentage- Deep learning reveals structures of thousands of compounds with promising point rise in flu-vaccination chemical compounds that could antibacterial properties. Like rates, there was a 6.5% fall in new drugs kill bacteria. Some of these halicin, these compounds antibiotic prescriptions — or With the pipeline of compounds were already used are structurally distinct from 14 fewer prescriptions for new antibiotics running as antibiotics; others came from existing antibiotics. The team every 1,000 people. This dry, researchers at the various natural products. hopes that this model or similar decrease was consistent across Massachusetts Institute of The team then tested its ones can continue to find new several antibiotic groups, Technology (MIT) in Cambridge trained model on about antibacterial compounds ripe including broad-spectrum have devised an automated 6,000 medical compounds from for possible drug development. penicillins, cephalosporins and helper to find antibacterial the Drug Repurposing Hub, tetracyclines. compounds. The machine- based at the Broad Institute of Cell 180, 688–702 (2020) The team points to a number learning system has discovered MIT and Harvard in Cambridge. of likely factors. Effective flu an antibiotic called halicin, The computer flagged one vaccines keep people from which is structurally different of these compounds, halicin, Molecular drills target seeking antibiotics (which are from most antibiotics and works as having bacteria-killing ineffective against flu), and against multidrug-resistant properties, even though it resistant bacteria vaccination limits antibiotic infections. was structurally distinct from A team at Texas A&M Health prescriptions for the secondary Antibiotics have typically known antibiotics. When the Science Center in Bryan bacterial infections that been found by testing soil team tested halicin on a range has developed microscopic

molecular drills that zero in on even when they are no longer the emergence of drug-resistant understand the problem, multidrug-resistant bacteria needed. This tendency, which bacteria and making the drugs researchers at the Genome and help to destroy them. The the researchers call genetic less effective in livestock. Institute of Singapore have light-activated drills, which can capitalism, compounds the In Latin America, meat created the first comprehensive spin at 3 million rotations per difficulty of wiping out drug- consumption has risen by more map of antibiotic-resistance second, work by mechanically resistant bacterial strains. than 40% since 2000; in Africa genes in bacteria found in penetrating the thick cell walls According to a principle and Asia, it has spiked by more a Singapore hospital. They of the bacteria. After this initial called stabilizing selection, than 60%. Given the magnitude hope that medical facilities breach, the researchers report, many genes drop out of the of these shifts, epidemiologist worldwide will develop similar conventional antibiotics are bacterial genome when they Thomas Van Boeckel and maps to monitor and control more effective against the no longer provide survival colleagues wanted to see resistant bacteria populations. microbes. benefits. But after sequencing how increased consumption Systems biologist Kern Rei One reason that bacteria the genomes of more than might be affecting bacterial Chng and colleagues took are difficult to kill is that many 29,000 strains of E. coli resistance to existing drugs. microbe samples at a variety have fortress-like cell walls dating from 1884 to 2018, The researchers compiled of sites around the hospital, consisting of two lipid bilayers biomathematician Colby Ford more than 900 data sets from including isolation rooms, and proteins that are cross- and his team concluded that Asia, Africa and South America bed rails, sink handles and linked with sugar molecules antibiotic-resistance genes recording the prevalence of clinical equipment, such as for strength; this makes were not dropping out of the antimicrobial resistance in pulse oximeters. They then them impregnable to many bacterial genome as much as animals. sequenced the genomes of the chemicals. However, these expected. After antibiotic use In pig and chicken farming, microbial community in each thick walls are no match for the became widespread around the proportion of drug location to get a clear picture molecular drills, which tunnel the middle of the twentieth compounds to which more than of what kind of bacteria were straight through them. century, the researchers note, 50% of target pathogens had present. In a series of trials, Jeffrey E. coli would have had to hoard developed resistance nearly The completed gene map Cirillo and colleagues found that antibiotic-resistance genes to tripled between 2000 and 2018. revealed where bacteria with the nanomachines destroyed survive. Resistance to antibiotics used in antibiotic-resistant properties up to 17% of drug-resistant The few resistance genes cattle also increased, although were most likely to dwell. Klebsiella pneumoniae bacteria that did fade were ones that less steeply. The highest rates For instance, the team found on their own. However, when demanded a high level of of resistance affected the bacterial genes for resistance the drills were used with the energy consumption, such as antibiotics most commonly to vancomycin, a common antibiotic meropenem, the kill those coding for processes that used in livestock, such as antibiotic, only on bed rails rate was as high as 94%. physically push the antibiotic tetracyclines, sulfonamides and and in bedside cabinets, The drills are activated by out of the bacterial cell. The penicillins. whereas genes for tetracycline light, so their greatest initial research suggests, therefore, The researchers flagged resistance appeared only in sink usefulness might be in treating that taking certain antibiotics Egypt, northeast India and aerators. Findings such as these resistant bacteria in places out of circulation for an central Mexico as some of can help hospitals to adjust that can easily be illuminated, extended period to reduce the hotspots for antibiotic their cleaning and prevention such as skin wounds, infected resistance, before gradually resistance. They recommend protocols, by focusing on areas catheters or surface infections reintroducing them — a strategy that livestock industries in that pose the highest infection elsewhere on the body. known as antibiotic cycling — is at-risk countries ramp up their risk. Eventually, the drills could likely to be more effective for surveillance of antimicrobial With high-volume genetic be used to treat bladder and drugs, such as tetracycline, resistance and curtail antibiotic sequencing becoming ever lung infections if a suitable light that require bacteria to spend use so that the drugs remain more affordable, the team urges source can be snaked in. considerable energy resisting. effective. Sustainable farming other hospitals to conduct practices that give animals their own on-site surveys of ACS Nano 13, 14377–14387 (2019) Cladistics https://doi.org/d9qt more space to move around antibiotic-resistant microbes. (2020) and reduce their stress might Detailed, tailored gene maps also help farmers to limit drug will inform efforts to wipe out Resistance genes resistance. pockets of resistant bacteria — Meat consumption and to prevent newer bacteria show persistence Science 365, eaaw1944 (2020) gaining a foothold. Genes that impart antimicrobial drives resistance resistance are all but certain to As lower-income countries Nature Med. 26, 941–951 (2020) take up permanent residence grow wealthier, researchers Hospital maps in a bacterium. Researchers at the Swiss Federal Institute at the University of North of Technology (ETH) in Zurich resistant microbes For the latest Carolina at Charlotte report report, their consumption of Hospitals have emerged as research published that, once antibiotic-resistance dairy and meat products rises. one of the main breeding online by Nature visit: genes appear, they persist This leads to farmers using grounds for antibiotic-resistant https://go.nature. com/2ghzk1s in Escherichia coli genomes more antibiotics, prompting infections in people. To better