Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Species identification in the water bottle

12.01.2018

Environmental DNA analysis makes it possible to detect water organisms without having to capture them first. For the first time, a team at the Technical University of Munich (TUM) systematically investigated the effect of various environmental factors on environmental DNA analyses. By doing so, the researchers have made an important step towards the standardized application of this method for the monitoring of water bodies.

DNA that animals release into aquatic environment can be detected using molecular analysis. This detection method is called environmental DNA (eDNA) A simple water sample is sufficient for this technique.


Environmental DNA analysis makes it possible to detect aquatic organisms without having to catch them: Bernhard Stoeckle (right) fetches a water bottle with liquid from a stream.

Photo: A. Heddergott/ TUM

However, this method does not work equally well in all water bodies and is therefore very likely to be influenced by the respective conditions in each body of water. This may include organic and inorganic components in the water or the flow conditions. So far, there is almost no research on how strongly the individual factors affect the analysis procedure.

Dr. Bernhard Stoeckle and Dr. Sebastian Beggel, researchers at the Chair of Aquatic Systems Biology and the Unit of Molecular Zoology (Chair of Zoology) at TUM investigated the influence of a wide range of environmental factors on eDNA analysis in an experiment. The idea for the experiment was based on a previous eDNA study on a native mussel species.

Systematic experimental structure

In a systematic laboratory setup, fish belonging to an invasive species — the round goby (Neogobius melanostomus) — were kept in aquaria in varying densities, under various flow conditions, with and without sediment, and were removed from the water after a defined period of time.

Subsequently, the researchers took water samples at regular intervals over a period of six days in order to be able to evaluate the efficiency of the eDNA analysis over time as well. In addition, the researchers added several substances, which could potentially hinder molecular analysis such as algae, humic substances, and inorganic suspended particles to the water, which are also found in natural ecosystems.

“That’s particularly important, otherwise we wouldn’t be able to apply the findings to eDNA studies in the field,” Bernhard Stoeckle explained. In order to find out which factors have the greatest influence, the researchers then compared the eDNA results of all water samples with each other.

Extent of influence of factors changes over time

On the one hand, the evaluation of the experiment showed that, over its entire duration, the flow conditions, the existence or absence of sediment, and the fish density only had an effect on the analyses in combination with each other. On the other hand, it turned out that the extent of the influence of the factors changed greatly over time.

Of the inhibitors added, organic substances (humic substances) interfered with the analyses the most. They often entirely precluded the successful application of the method. DNA could only be detected in 41 percent of the samples examined. Algae also had a comparable effect, albeit less pronounced. “Our findings clearly demonstrate how important it is that environmental conditions are also taken into account when performing eDNA analyses in order to be able to correctly interpret the findings,” said Bernhard Stoeckle.

Based on the results of the experiment, it can be concluded that specific environmental conditions interfere greatly with environmental DNA experiments, in some cases making it difficult or even impossible to detect species.

Pictures for editorial coverage

Publication:
Stoeckle, BC., Beggel, S., Cerwenka, AF., Motivans, E., Kuehn, R., Geist, J.: A systematic approach to evaluate the influence of environmental conditions on eDNA detection success in aquatic ecosystems, PLoS One 12/2017.
DOI: 10.1371/journal.pone.0189119.

Contact:
Prof. Dr. Jürgen Geist
Technical University of Munich
Chair of Aquatic Systems Biology
Phone: +49/8161/71-3974
Mail: geist@wzw.tum.de
http://fisch.wzw.tum.de

Weitere Informationen:

https://www.tum.de/nc/en/about-tum/news/press-releases/detail/article/34398/ article
https://mediatum.ub.tum.de/1427106?id=1427106 pictures

Dr. Ulrich Marsch | Technische Universität München

More articles from Life Sciences:

nachricht Fish recognize their prey by electric colors
13.11.2018 | Rheinische Friedrich-Wilhelms-Universität Bonn

nachricht The dawn of a new era for genebanks - molecular characterisation of an entire genebank collection
13.11.2018 | Leibniz-Institut für Pflanzengenetik und Kulturpflanzenforschung

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: A Chip with Blood Vessels

Biochips have been developed at TU Wien (Vienna), on which tissue can be produced and examined. This allows supplying the tissue with different substances in a very controlled way.

Cultivating human cells in the Petri dish is not a big challenge today. Producing artificial tissue, however, permeated by fine blood vessels, is a much more...

Im Focus: A Leap Into Quantum Technology

Faster and secure data communication: This is the goal of a new joint project involving physicists from the University of Würzburg. The German Federal Ministry of Education and Research funds the project with 14.8 million euro.

In our digital world data security and secure communication are becoming more and more important. Quantum communication is a promising approach to achieve...

Im Focus: Research icebreaker Polarstern begins the Antarctic season

What does it look like below the ice shelf of the calved massive iceberg A68?

On Saturday, 10 November 2018, the research icebreaker Polarstern will leave its homeport of Bremerhaven, bound for Cape Town, South Africa.

Im Focus: Penn engineers develop ultrathin, ultralight 'nanocardboard'

When choosing materials to make something, trade-offs need to be made between a host of properties, such as thickness, stiffness and weight. Depending on the application in question, finding just the right balance is the difference between success and failure

Now, a team of Penn Engineers has demonstrated a new material they call "nanocardboard," an ultrathin equivalent of corrugated paper cardboard. A square...

Im Focus: Coping with errors in the quantum age

Physicists at ETH Zurich demonstrate how errors that occur during the manipulation of quantum system can be monitored and corrected on the fly

The field of quantum computation has seen tremendous progress in recent years. Bit by bit, quantum devices start to challenge conventional computers, at least...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

“3rd Conference on Laser Polishing – LaP 2018” Attracts International Experts and Users

09.11.2018 | Event News

On the brain’s ability to find the right direction

06.11.2018 | Event News

European Space Talks: Weltraumschrott – eine Gefahr für die Gesellschaft?

23.10.2018 | Event News

 
Latest News

The dawn of a new era for genebanks - molecular characterisation of an entire genebank collection

13.11.2018 | Life Sciences

Fish recognize their prey by electric colors

13.11.2018 | Life Sciences

Ultrasound Connects

13.11.2018 | Awards Funding

VideoLinks
Science & Research
Overview of more VideoLinks >>>