Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Deceptively simple: Minute marine animals live in a sophisticated symbiosis with bacteria

11.06.2019

Trichoplax, one of the simplest animals on Earth, lives in a highly specific and intimate symbiosis with two types of bacteria. The first, Grellia, is related to parasitic bacteria that cause typhus and Rocky Mountain spotted fever. Intriguingly, Grellia does not appear to harm Trichoplax. The second, Ruthmannia, sits inside the cells Trichoplax uses to digest its food. The Trichoplax symbiosis provides a window into the microbial dark matter - poorly described groups of bacteria. The study by scientists from the Max Planck Institute for Marine Microbiology and the University of Hawaii has now been published in the journal Nature Microbiology.

Trichoplax is one of the simplest animals one can imagine, and looks like a shapeless little blob. Senior author Nicole Dubilier says it reminds her of a potato chip. Trichoplax lives in warm coastal waters around the world, where it grazes on microscopic algae that cover sand and rocks. Although most aquarists may not know it, Trichoplax can also be found in almost any saltwater aquarium with corals.


Trichoplax eating.

Photo: Michael Hadfield / University of Hawaii


In the trap: Colonized Trichoplax traps suspended in shallow water under a footbridge.

Photo: Harald Gruber-Vodicka / Max Planck Institute for Marine Microbiology

Trichoplax, together with sponges and jellyfish, belongs to one of the most basal lineages of the animal kingdom. Until the 70ies, it was not even clear if Trichoplax is a proper, fully-grown animal or just the juvenile stage of a jellyfish.

Only about a half a millimetre in diameter, these animals lack a mouth, gut and any other organs, and are made up of only six different kinds of cells. Its simplicity makes it a popular model organism for biologists.


Scientists from the Max Planck Institute for Marine Microbiology in Bremen, Germany, the University of Hawaii and North Carolina State University have now discovered that Trichoplax is not as simple as it looks. It lives in a remarkably sophisticated symbiosis with highly unusual bacteria.

Simple is beautiful

The first observation of bacteria in Trichoplax was nearly 50 years ago by the German zoologist Karl Grell. But no one has really taken a closer look since then. An international group of scientists around Harald Gruber-Vodicka, Niko Leisch and Nicole Dubilier from the Max Planck Institute for Marine Microbiology, and Michael Hadfield from the University of Hawaii have now investigated the bacterial tenants of Trichoplax by sequencing their genomes and using high-resolution microscopy to see where they live.

“Despite being so simple, Trichoplax harbors two very different and highly unusual bacterial symbionts in its cells,” says Gruber-Vodicka. “Both symbionts are very picky – or cell-specific, as we call it. Each symbiont lives in only one type of host cell.”

Grellia – the first known symbiont to live in the endoplasmic reticulum

One symbiont, named Grellia after the zoologist Karl Grell, lives inside the endoplasmic reticulum (ER) of Trichoplax, and is the first symbiont known to permanently live in an animal's ER. The ER plays a central role in protein and membrane production. Proving that Grellia is truly in the ER was challenging.

“We reconstructed a detailed three-dimensional model of the ER to show that Grellia lives inside of it, supported by the electron microscopy facility of the Max Planck Institute of Molecular Cell Biology and Genetics in Dresden,” Niko Leisch explains. “Other parasitic bacteria imitate the structure of the ER to trick the hosts into thinking they are not harmful. However, our imaging data clearly showed that Grellia lives inside its host's ER.”

Intriguingly, Grellia, although closely related to parasites, doesn't appear to be harmful for Trichoplax. “Although it has genes that would allow it to steal energy from its host, it does not use them,” Leisch continues.

Ruthmannia – seeing microbial dark matter

The second symbiont of Trichoplax, Ruthmannia, belongs to a group of bacteria that were only recently discovered, the Margulisbacteria. “Before our study, Margulisbacteria were part of the so-called microbial dark matter – the vast majority of microbial organisms that biologists find through sequencing, but are unable to culture,” explains Harald Gruber-Vodicka. “We have never actually seen them, even though their genetic traces were found in aquatic samples all over the globe.” Now Gruber-Vodicka and Leisch took the first images of a Margulisbacteria.

“It’s the first time we could see a member of this group. For us, observing this microbial dark matter was just as exciting as imaging black holes.” This symbiont lives in cells that Trichoplax uses to digest its algal food. "Ruthmannia appears to only eat the fats and other lipids of the algae, and leaves the rest to its host. In return, we think Ruthmannia may provide Trichoplax with vitamins and amino acids." With Trichoplax thriving in the lab cellars of the Max Planck Institute for Marine Microbiology, the authors now have continuous access to this enigmatic group of bacteria.

What’s next

“In this study, we focused on the symbiotic partners of a single Trichoplax species,” says Nicole Dubilier, Director at the Max Planck Institute for Marine Microbiology. “However, at least 20 more species have been described, and our first results indicate that each host species has its own, very specific set of symbionts. We are excited about taking a closer look at this remarkable diversity and how it evolved. These tiny animals not only look like potato chips, they also pack a crunch when it comes to what's inside them.”


Participating institutions

Max Planck Institute for Marine Microbiology, Bremen, Germany
University of Hawaiʻi at Mānoa, Honolulu, USA 

North Carolina State University, Raleigh, North Carolina, USA
University of Calgary, Alberta, Canada

Wissenschaftliche Ansprechpartner:

Dr. Harald Gruber-Vodicka
Department of Symbiosis
Max Planck Institute for Marine Microbiology, Bremen, Germany
Phone: +49 421 2028-760
E-Mail: hgruber@mpi-bremen.de

Prof. Dr. Nicole Dubilier
Department of Symbiosis
Max Planck Institute for Marine Microbiology, Bremen, Germany
Phone: +49 421 2028-932
E-Mail: ndubilier@mpi-bremen.de

Dr. Fanni Aspetsberger
Press Officer
Max Planck Institute for Marine Microbiology, Bremen, Germany
Phone: +49 421 2028-947
E-Mail: faspetsb@mpi-bremen.de

Originalpublikation:

Harald R. Gruber-Vodicka, Nikolaus Leisch, Manuel Kleiner, Tjorven Hinzke, Manuel Liebeke, Margaret McFall-Ngai, Michael G. Hadfield, Nicole Dubilier: Two intracellular and cell type-specific bacterial symbionts in the placozoan Trichoplax H2. Nature Microbiology. DOI: 10.1038/s41564-019-0475-9

Weitere Informationen:

https://www.mpi-bremen.de/en/Page3587.html

Dr. Fanni Aspetsberger | Max-Planck-Institut für Marine Mikrobiologie

More articles from Life Sciences:

nachricht Learning from Nature’s Bounty: New Libraries for Drug discovery
11.06.2019 | Universität Basel

nachricht The rare African Golden Cat photographed for the first time in Tanzania
11.06.2019 | MUSE Museo delle Scienze

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Cost-effective and individualized advanced electronic packaging in small batches now available

Fraunhofer IZM is joining the EUROPRACTICE IC Service platform. Together, the partners are making fan-out wafer level packaging (FOWLP) for electronic devices available and affordable even in small batches – and thus of interest to research institutes, universities, and SMEs. Costs can be significantly reduced by up to ten customers implementing individual fan-out wafer level packaging for their ICs or other components on a multi-project wafer. The target group includes any organization that does not produce in large quantities, but requires prototypes.

Research always means trying things out and daring to do new things. Research institutes, universities, and SMEs do not produce in large batches, but rather...

Im Focus: 2D crystals conforming to 3D curves create strain for engineering quantum devices

A team led by scientists at the Department of Energy's Oak Ridge National Laboratory explored how atomically thin two-dimensional (2D) crystals can grow over 3D objects and how the curvature of those objects can stretch and strain the crystals. The findings, published in Science Advances, point to a strategy for engineering strain directly during the growth of atomically thin crystals to fabricate single photon emitters for quantum information processing.

The team first explored growth of the flat crystals on substrates patterned with sharp steps and trenches. Surprisingly, the crystals conformally grew up and...

Im Focus: Experiments and calculations allow examination of boron's complicated dance

Work opens a path to precise calculations of the structure of other nuclei.

In a study that combines experimental work and theoretical calculations made possible by supercomputers, scientists have determined the nuclear geometry of two...

Im Focus: Fraunhofer HHI and IAF demonstrate the first wireless real-time video transmission using Terahertz

The Fraunhofer Heinrich Hertz Institute HHI develops next-generation wireless transmission systems (Beyond 5G) based on Terahertz (THz) technologies. The THz technology supports significantly higher data transmission rates than current 4G and 5G mobile wireless technologies. Researchers of the department Photonic Networks and Systems, in collaboration with the Fraunhofer Institute for Applied Solid State Physics IAF, have succeeded in transmitting a 4K video in real-time over a wireless THz link. This was the first time this technology was successfully realized in a real-time experiment. A wireless transmission capacity of 100 Gbit/s was demonstrated over the THz link.

Requirements placed on transmission capacities in communication networks are continuously growing, driven by new applications such as Industry 4.0, autonomous...

Im Focus: Colliding lasers double the energy of proton beams

Researchers from Sweden's Chalmers University of Technology and the University of Gothenburg present a new method which can double the energy of a proton beam produced by laser-based particle accelerators. The breakthrough could lead to more compact, cheaper equipment that could be useful for many applications, including proton therapy.

Proton therapy involves firing a beam of accelerated protons at cancerous tumours, killing them through irradiation. But the equipment needed is so large and...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

SEMANTiCS 2019 brings together industry leaders and data scientists in Karlsruhe

29.04.2019 | Event News

Revered mathematicians and computer scientists converge with 200 young researchers in Heidelberg!

17.04.2019 | Event News

First dust conference in the Central Asian part of the earth’s dust belt

15.04.2019 | Event News

 
Latest News

Organic electronics: a new semiconductor in the carbon-nitride family

07.06.2019 | Materials Sciences

Radon inferior to radium for electric dipole moments (EDM) searches

07.06.2019 | Physics and Astronomy

NIH HIV experts prioritize research to achieve sustained ART-free HIV remission

07.06.2019 | Life Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>