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Environment and sustainability

Antibiotic resistance may develop in the sea

We mostly associate the development of antibiotic resistance with herds of pigs or hospitals. However, the genes that create the resistance originate in many diverse habitats in which there are microorganisms – including the world’s oceans and seas, which have large and complex microbial communities. A new international research article with Danish participation describes this.

The research published in Frontiers in Microbiology focuses on microbial communities in marine sponges that otherwise are normally hidden from humans. Sponges are animals but have no cell membranes, tissue or organs, and there are about 10,000 types. Their bodies are configured to maximize the flow of water through the body. The sponges feed on the small marine particles and on the microorganisms with which they live in close symbiosis.

The microorganisms that live in the sponges are able to produce several antibiotic substances that can be used against bacteria. The production of these antibiotics also makes sponges an ideal place to search for antibiotic resistance. The researchers examined three types of sponges in the Mediterranean Sea for resistance genes: Aplysina aerophoba, Petrosia ficiformis and Corticium candelabrum.

The researchers initially looked for sponges based on gene sequences that are similar to known resistance genes and found 37 suitable genes that coded for resistance to 14 common antibiotics used by humans. The results suggest that microbial communities living in sponges may be a reservoir for many more previously undiscovered resistance genes.

Because resistance genes spread from organism to organism, the marine environment may thus potentially harbour an enormous reservoir of possible resistance genes that can cause problems for human health. The massive use of antibiotics for humans and animals in recent decades has led to the evolution of multidrug-resistant microorganisms, resulting in poorer options for treating bacterial infections. The microbes in marine sponges are naturally also a potential way of discovering new antibiotics – but that is a completely different story.

Sponge microbiota are a reservoir of functional antibiotic resistance” has been published in Frontiers in Microbiology and was co-authored by researchers from the Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark.

Morten Otto Alexander Sommer
Our work is broadly aimed towards understanding how biological systems establish, organize and evolve. We use cutting edge technology and aim to translate our basic research findings into entities, policies and education that provide long term benefits to society. Antibiotic resistance Evolution is rendering our medicines against many infections useless threatening to bring us back to the pre-antibiotic era. In many cases resistance to a particular antibiotic did not evolve within the resistant human pathogen, but rather was acquired by lateral gene transfer from other resistant bacteria. These resistant donor bacteria need not be pathogenic, yet they contribute to the evolution of antibiotic resistance in human pathogens by serving as an accessible reservoir of resistance genes. We are using a variety of culture-dependent and culture-independent methods to characterize how these reservoirs are interacting, with the ultimate goal of creating quantitative models for how antibiotic resistance genes arise in human pathogens. We study the adaptive mechanisms of drug resistance and collateral sensitivity using a combination of laboratory evolution and sampling of clinical isolates, with the goal of developing novel treatment strategies for countering resistance development. Synthetic biology for sustainable generation of value chemicals Increasing concerns related to climate change caused by our reliance on fossil fuels for many processes in our society prompt the need to look for alternatives. Biological systems can be engineered to perform conversions of renewable input substrates to value added products using much less energy than conventional methods. We use a variety of metagenomic and culture based techniques for harnessing biological diversity useful for generation of biofuels and other value chemicals. We build synthetic selection networks that sense and respond to specific metabolites inside the cell. We deploy these tools for pathway discovery, strain optimization for specific metabolic engineering targets. We use synthetic selection systems for multiplexed interrogation of biological phenotypes enhancing our understanding of cellular metabolism and regulation. Human microbiome and engineered microbiome therapeutics The human microbiome is to an increasing extent being implicated in a wide range of disease and health states. We study the human microbiome during interventions, with a particular focus on antibiotic treatment and resulting microbiome modulation. We design and build new interventions for modulating the microbiome to promote specific community compositions or functionality. We also design and build interventions that can amend the functionality encoded in the gut microbiome.