Antibiotic resistance is spreading faster than previously thought

Antibiotic resistance is spreading faster than previously thought

We are searching data for your request:

Forums and discussions:
Manuals and reference books:
Data from registers:
Wait the end of the search in all databases.
Upon completion, a link will appear to access the found materials.

New insights into antibiotic resistance

The increasing prevalence of antibiotic-resistant pathogens poses a significant threat and many bacterial infectious diseases that have so far been controllable could become a deadly danger in the future. Using the example of fish from aquaculture, a research team has now been able to gain new insights into the mechanisms of transmission of antibiotic resistance between bacteria. These are more diverse than previously thought.

Microorganisms resistant to a wide range of substances

"The use of antibiotics in human and veterinary medicine has increased steadily over the past 70 years and has led to a dramatic increase in resistant microorganisms," says Prof. Dr. Michael Schloter, Head of the Comparative Microbiome Analysis (COMI) department at Helmholtz Zentrum München. It is particularly dramatic that many microorganisms are not only resistant to an antibiotic, but to a large number of different substances. This makes the treatment of infectious diseases particularly difficult, according to the scientist. "We wanted to find out which mechanisms underlie the development of resistance," said Schloter. Her study results were published in the specialist magazine "Microbiome".

In the current study, Professor Schlotter, together with his team and Danish scientists around Gisle Vestergaard (University of Copenhagen and Helmholtz Center Munich) examined fish from an aquaculture: Specifically, it was about Piaractus mesopotamicus, a species known as Pacu from South America, which is often found in aquacultures is held. The animals received the antibiotic Florfenicol with food over 34 days. During and afterwards, the scientists took samples from the digestive tract and looked for corresponding genetic changes in the bacteria resident there.

Resistance leaps through the genome

"As expected, the administration of the antibiotic led to an increase in the genes that are responsible for corresponding resistance," explains COMI doctoral student Johan Sebastian Sáenz Medina, first author of the work. Examples include genes for pump proteins that simply transport the active ingredient back out of the bacteria. "What was particularly interesting for us was the increasing number of so-called mobile genetic elements in the vicinity of these resistance genes," adds Sáenz Medina. This suggested that the bacteria also exchange resistance with one another through viruses - so-called phages - and transposons.

Plasmids are solely responsible for the exchange of resistance genes

Further metagenomic investigations confirmed that these mobile genetic elements jump across the genome, entraining parts of the genome - including the resistance genes - and reinserting them elsewhere. So far, it was assumed that so-called plasmids (in simple terms, easily transferable mini-chromosomes) are responsible for the exchange of resistance genes.

Study result

"The finding that resistance is also transferred between bacteria on a large scale apart from plasmids is quite surprising," concludes Professor Schloter about the current study. “Building on this, appropriate models of expansion should be checked and adjusted. In addition, our data definitely stimulates thought as to whether and to what extent the increasing number of aquacultures worldwide should be operated with antibiotics, ”summarizes the study director. (fm)

Author and source information

Video: We are running out of effective antibiotics fast (November 2022).