DISTRIBUTION OF ANTIBIOTIC RESISTANCE GENES IN THE ENVIRONMENT:
THE ROLE OF MINERAL FACILITATED HORIZONTAL GENE TRANSFER
Combining recent research across disciplines, I see evidence that minerals hold a high and unrecognized potential for enhancing the distribution of the ARg in the environment. Adsorption of ARg to minerals significantly increases the ARg’s lifetime and facilitates their distribution by sedimentary transport processes. In addition, minerals also serve as a) sites for horizontal gene transfer (HGT), b) platforms for microbial growth and, hence 3) act as hot spots for propagation of adsorbed ARg to other microbes. However, some minerals and ARg are bound more strongly than others and various bacteria have different affinities toward various minerals. Those variations in affinity are poorly quantified but vital for predicting the distribution of ARg in the environment.
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Bacterial colony formation.
Image by Lisselotte Jauffred (collaborator from NBI)
The spread of antibiotic resistance genes (ARg) is a worldwide health risk1 and is no longer only a clinical issue. Vast reservoirs of ARg are found in natural environments2–4 such as soils, sediments and oceans. The emergence and release of ARg to the environment is in particular caused by extended use of antibiotics in farming, e.g. where the genes dissipate from the manure.5 Once in the environment, the ARg are surprisingly rapidly propagated. It is well known that the ARg are distributed to neighbour bacteria through processes of both cell sharing or through horizontal gene transfer (HGT) where one species acquirer resistance from another.6,7 Most HGT responsible for the spread of ARg are assumed to be through direct microbe-microbe contact. However, I find that the outcome of non-contact transfer is grossly underestimated. In the HGT mechanism called “Transformation”, free ARg in suspension or adsorbed to a mineral can be picked up and incorporated into non-related organisms. Considering that free DNA only can survive for a few weeks in sea- and freshwater environments,8–10 any HGT from free DNA can rightly be assumed to be local, but if the DNA gets adsorbed to a mineral, it can survive for several hundred thousands of years.11–14 If this also holds for ARg, then minerals offer a potent mechanism for distributing ARg through our environments my means of sedimentary processes.
Karina K. Sand
Associate Professor
Orcid ID: 0000-0002-0720-7229
Email:
Work: kks@sund.ku.dk
Address:
Øster Voldgade 7
1350 CPH K
Denmark
Totals
Summary
- Grant value as sole PI: ~2,804,800 EUR,
- Research stays. USA, UK. Aarhus.
- Abroad employment: USA: 1.5 yr, UK: 3 yr.
- Peer reviewed papers: 38
- Papers submitted: /
- Preprints pending review: 2
- H-index 20 (G-scholar Jan. 2025)
Experimentalist working on the interface between geology, geochemistry, geomicrobiology and biophysics.
Specialty: Liquid cell in-situ techniques to explore and quantify bio-mineral interactions and dynamics.
Education
2008-2011
PhD Fellow
UNIVERSITY OF COPENHAGEN. DENMARK
Dept Chemistry. Faculty of Science.
Topic: Biomineralization and growth inhibition by functional groups.
2007
MSc.
UNIVERSITY OF COPENHAGEN. DENMARK
Dept of Geology. Faculty of Science
Topic: Geothermobarometric. Diamond potential of the mantle in southern west Greenland
Positions
2019– current
Molecular Geobiology
Associate Professor.
GLOBE institute, Faculty of Health and Medical Sciences, UCPH.
2018 – 2019
BioGeoChemistry
Associate Professor.
Dept. of Chemistry, Faculty of Science, UCPH, DK
2016 – 2020
BioGeoChemistry
Ser Cymru II Research Fellow.
Geography& Earth Sciences, University of Aberystwyth. UK.
2012 – 2018
Biomineralization
Assistant Professor
Dept. of Chemistry, Faculty of Science, UCPH, DK
2014 – 2016
Bio-mineral-microbe
Research Associate.
Physical Science Division, Pacific NW National Laboratory, USA
2013 – 2014
Molecule-mineral-microbe
Visiting Scholar.
Molecular Foundry, Lawrence Berkeley National Laboratory, USA
2011 – 2012
Biomineralization
Postdoctoral Fellow.
Dept. of Chemistry, Faculty of Science, UCPH, DK
Funding
Principle Investigator and sole applicant
2022 – 2026
~670.000 EUR
Carlsberg Foundation Young Researcher Fellowship
Mineral facilitated horizontal gene transport. -A new principle for the evolution of life?
2019 – 2024
~1.326.700 EUR
VILLUM Young Investigator
Propagation of antibiotic resistance genes in the environment: the role of mineral facilitated horizontal gene transfer.
~110.000 EUR
2018 – 2020
DFF-Danish ERC-programme grant
The significance of minerals in horizontal gene transfer: A new principle for evolution of life?
~322.500 EUR
2016 – 2020
Ser Cymru II Research Fellow
Kinetic and thermodynamic controls on CaCO3 formation during geologic carbon storage; constraining and applying the influence of bacteria and clay.
~126,030 EUR
2015 – 2016
Sapere Aude Research Talent grant
The influence of electron transport and charge density on precipitation, growth and transformation of iron oxides in microbial systems
2014 – 2015
~102,200 EUR
Research Fellowship at National Labs, USA
Extracellular influence on precipitation, growth and transformation mechanisms of iron oxides in microbial systems.
~147,800 EUR
2013 – 2014
Individual Post doc grant
Extracellular influence on precipitation, growth and transformation mechanisms of iron oxides in microbial systems.
Collaborative grants
2024 – 2027 ~676,700 EUR
Exploratory Interdisciplinary Synergy Programme
4 PI´s
2023 – 2024 ~80,300 EUR
Project in the startup Category
Main PI
DNRF Center of excellence:
Ancient environmental genomics.
Co-PI
2023 – 2028 ~9,800,000 EUR
Principal Investigator and host of EU HORISON Postdoctoral Fellows
2024 – 2026 ~230,774 EUR
Marie Skłodowska-Curie Actions: Individual Fellowship for Taru Verma
2021 – 2023 ~219,312 EUR
Marie Skłodowska-Curie Actions: Individual Fellowship for Oluwatoosin Bummi Adebayo Agbaje
2020 – 2022 ~219,312 EUR
Marie Skłodowska-Curie Actions: Individual Fellowship for Ioannis Kontopoulos
