Individual cells can pass resistance genes to one another through a process called horizontal gene transfer, or by "transformation," the uptake of DNA from the environment.
Now researchers report that they can interrupt the cascade of cellular events that allows S. pneumoniae to swap or suck up DNA. The new findings, reported in the journal PLoS ONE, advance the effort to develop a reliable method for shutting down the spread of drug resistance in bacteria.
"Within the last few decades, S. pneumoniae has developed resistance to several classes of antibiotics," said University of Illinois pathobiology professor Gee Lau, who led the study. "Importantly, it has been shown that antibiotic stress – the use of antibiotics to treat an infection – can actually induce the transfer of resistance genes among S. pneumoniae. Our approach inhibits resistance gene transfer in all strains of S. pneumoniae, and does so without increasing selective pressure and without increasing the likelihood that resistant strains will become dominant."
Lau and his colleagues focused on blocking a protein that, when it binds to a receptor in the bacterial cell membrane, spurs a series of events in the cell that makes the bacterium "competent" to receive new genetic material. The researchers hypothesized that interfering with this protein (called CSP) would hinder its ability to promote gene transfer.
In previous work published late last year in the journal PLoS Pathogens, Lau's team identified proteins that could be made in the lab that were structurally very similar to the CSP proteins. These artificial CSPs can dock with the membrane receptors, block the bacterial CSPs' access to the receptors and reduce bacterial competence, as well as reducing the infectious capacity of S. pneumoniae.
In the new study, the researchers fine-tuned the amino acid structure of more than a dozen artificial CSPs and tested how well they inhibited the S. pneumoniae CSPs. They also tested their ability (or, more desirably, their inability) to mimic the activity of CSPs in bacterial cells.
"The chemical properties of individual amino acids in a protein can greatly influence the protein's activity," Lau said.
The team identified several artificial CSPs that both inhibited the bacterial CSPs and reduced S. pneumoniae competence by more than 90 percent.
"This strategy will likely help us reduce the spread of antibiotic-resistance genes among S. pneumoniae and perhaps other species of streptococcus bacteria," Lau said.
The study team included researchers from Sun-Yat-Sen University in Guangdong, China. The National Institutes of Health and the University of Illinois Research Board Arnold O. Beckman Research Endowment partially supported this work.
Editor's notes: To reach Gee Lau, call 217-333-5077; email email@example.com.
The paper, "Saturated Alanine Scanning Mutagenesis of the Pneumococcus Competence Stimulating Peptide Identifies Analogs That Inhibit Genetic Transformation," is available online.
Diana Yates | EurekAlert!
Staying in Shape
16.08.2018 | Max-Planck-Institut für molekulare Zellbiologie und Genetik
Chips, light and coding moves the front line in beating bacteria
16.08.2018 | Okinawa Institute of Science and Technology (OIST) Graduate University
Scientists at the University of California, Los Angeles present new research on a curious cosmic phenomenon known as "whistlers" -- very low frequency packets...
Scientists develop first tool to use machine learning methods to compute flow around interactively designable 3D objects. Tool will be presented at this year’s prestigious SIGGRAPH conference.
When engineers or designers want to test the aerodynamic properties of the newly designed shape of a car, airplane, or other object, they would normally model...
Researchers from TU Graz and their industry partners have unveiled a world first: the prototype of a robot-controlled, high-speed combined charging system (CCS) for electric vehicles that enables series charging of cars in various parking positions.
Global demand for electric vehicles is forecast to rise sharply: by 2025, the number of new vehicle registrations is expected to reach 25 million per year....
Proteins must be folded correctly to fulfill their molecular functions in cells. Molecular assistants called chaperones help proteins exploit their inbuilt folding potential and reach the correct three-dimensional structure. Researchers at the Max Planck Institute of Biochemistry (MPIB) have demonstrated that actin, the most abundant protein in higher developed cells, does not have the inbuilt potential to fold and instead requires special assistance to fold into its active state. The chaperone TRiC uses a previously undescribed mechanism to perform actin folding. The study was recently published in the journal Cell.
Actin is the most abundant protein in highly developed cells and has diverse functions in processes like cell stabilization, cell division and muscle...
Scientists have discovered that the electrical resistance of a copper-oxide compound depends on the magnetic field in a very unusual way -- a finding that could help direct the search for materials that can perfectly conduct electricity at room temperatur
What happens when really powerful magnets--capable of producing magnetic fields nearly two million times stronger than Earth's--are applied to materials that...
08.08.2018 | Event News
27.07.2018 | Event News
25.07.2018 | Event News
16.08.2018 | Life Sciences
16.08.2018 | Earth Sciences
16.08.2018 | Life Sciences