Low levels of these chemicals, called biocides, can make the potentially lethal bacterium Staphylococcus aureus remove toxic chemicals from the cell even more efficiently, potentially making it resistant to being killed by some antibiotics.
Biocides are used in disinfectants and antiseptics to kill microbes. They are commonly used in cleaning hospitals and home environments, sterilizing medical equipment and decontaminating skin before surgery. At the correct strength, biocides kill bacteria and other microbes. However, if lower levels are used the bacteria can survive and become resistant to treatment.
"Bacteria like Staphylococcus aureus make proteins that pump many different toxic chemicals out of the cell to interfere with their antibacterial effects," said Dr Glenn Kaatz from the Department of Veterans Affairs Medical Center in Detroit, USA. "These efflux pumps can remove antibiotics from the cell and have been shown to make bacteria resistant to those drugs. We wanted to find out if exposure to biocides could also make bacteria resistant to being killed by the action of efflux pumps."
The researchers exposed S. aureus taken from the blood of patients to low concentrations of several biocides and dyes, which are also used frequently in hospitals. They looked at the effect of exposure on the bacteria and found that mutants that make more efflux pumps than normal were produced.
"We found that exposure to low concentrations of a variety of biocides and dyes resulted in the appearance of resistant mutants," said Dr Kaatz. "The number of efflux pumps in the bacteria increased. Because the efflux pumps can also rid the cell of some antibiotics, pathogenic bacteria with more pumps are a threat to patients as they could be more resistant to treatment."
If bacteria that live in protected environments are exposed to biocides repeatedly, for example during cleaning, they can build up resistance to disinfectants and antibiotics. Such bacteria have been shown to contribute to hospital-acquired infections.
"Scientists are trying to develop inhibitors of efflux pumps. Effective inhibitors would reduce the likelihood of additional resistance mechanisms emerging in bacteria," said Dr Kaatz. "Unfortunately, inhibitors evaluated to date do not work on a wide range of pathogens so they are not ideal to prevent resistance."
"Careful use of antibiotics and the use of biocides that are not known to be recognised by efflux pumps may reduce the frequency at which resistant strains are found," said Dr Kaatz. "Alternatively, the combination of a pump inhibitor with an antimicrobial agent or biocide will reduce the emergence of such strains and their clinical impact."
Lucy Goodchild | alfa
Unique brain 'fingerprint' can predict drug effectiveness
11.07.2018 | McGill University
Direct conversion of non-neuronal cells into nerve cells
03.07.2018 | Universitätsmedizin der Johannes Gutenberg-Universität Mainz
For the first time ever, scientists have determined the cosmic origin of highest-energy neutrinos. A research group led by IceCube scientist Elisa Resconi, spokesperson of the Collaborative Research Center SFB1258 at the Technical University of Munich (TUM), provides an important piece of evidence that the particles detected by the IceCube neutrino telescope at the South Pole originate from a galaxy four billion light-years away from Earth.
To rule out other origins with certainty, the team led by neutrino physicist Elisa Resconi from the Technical University of Munich and multi-wavelength...
For the first time a team of researchers have discovered two different phases of magnetic skyrmions in a single material. Physicists of the Technical Universities of Munich and Dresden and the University of Cologne can now better study and understand the properties of these magnetic structures, which are important for both basic research and applications.
Whirlpools are an everyday experience in a bath tub: When the water is drained a circular vortex is formed. Typically, such whirls are rather stable. Similar...
Physicists working with Roland Wester at the University of Innsbruck have investigated if and how chemical reactions can be influenced by targeted vibrational excitation of the reactants. They were able to demonstrate that excitation with a laser beam does not affect the efficiency of a chemical exchange reaction and that the excited molecular group acts only as a spectator in the reaction.
A frequently used reaction in organic chemistry is nucleophilic substitution. It plays, for example, an important role in in the synthesis of new chemical...
Optical spectroscopy allows investigating the energy structure and dynamic properties of complex quantum systems. Researchers from the University of Würzburg present two new approaches of coherent two-dimensional spectroscopy.
"Put an excitation into the system and observe how it evolves." According to physicist Professor Tobias Brixner, this is the credo of optical spectroscopy....
Ultra-short, high-intensity X-ray flashes open the door to the foundations of chemical reactions. Free-electron lasers generate these kinds of pulses, but there is a catch: the pulses vary in duration and energy. An international research team has now presented a solution: Using a ring of 16 detectors and a circularly polarized laser beam, they can determine both factors with attosecond accuracy.
Free-electron lasers (FELs) generate extremely short and intense X-ray flashes. Researchers can use these flashes to resolve structures with diameters on the...
13.07.2018 | Event News
12.07.2018 | Event News
03.07.2018 | Event News
17.07.2018 | Information Technology
17.07.2018 | Materials Sciences
17.07.2018 | Power and Electrical Engineering