Decreased iron levels in seawater make mussels loosen their grip

July 29, 2020

Mussels secrete sticky plaques that help them attach to wet surfaces, such as rocks on the beach. These adhesive structures are rich in iron, which is thought to help make the attachments strong yet flexible. Now, researchers reporting in Environmental Science & Technology have shown that mussels form weaker attachments in iron-deficient seawater, revealing a possible consequence of altered iron bioavailability in oceans.

As oceans become more acidic in a changing climate, iron dissolves and is less bioavailable to filter feeders, such as mussels, that strain iron particles from seawater. In mussels, iron helps cross-link proteins in the sticky plaques that attach to surfaces and adds mechanical toughness to the hair-like threads that link the plaque to the mollusk's inner tissues. Jonathan Wilker and colleagues at Purdue University wondered how mussels' ability to adhere to surfaces would be affected by changing iron levels in seawater.

To find out, the researchers cultured mussels in artificial seawater containing lower, normal and higher iron levels. The researchers grew the mussels in each water condition for three days, during which the creatures attached to aluminum plates. Then, the researchers cut off the threads near the shell and pulled upward on them, measuring the force needed to remove the plaque from the plate. As the concentration of iron in the water increased, so did the plaque's stickiness, except for the highest iron level, at which adhesion slightly decreased. The team also observed that the plaques became smaller and darker as the iron concentration increased, and the porous microstructure of the plaques became more pronounced. This study is the first to examine how changing iron levels affect the performance of a biological material in a whole animal, the researchers say.

The authors acknowledge funding from the Office of Naval Research, the National Science Foundation and the Purdue Research Foundation.
The paper's abstract will be available on July 29 at 8 a.m. Eastern time here:

The American Chemical Society (ACS) is a nonprofit organization chartered by the U.S. Congress. ACS' mission is to advance the broader chemistry enterprise and its practitioners for the benefit of Earth and its people. The Society is a global leader in providing access to chemistry-related information and research through its multiple research solutions, peer-reviewed journals, scientific conferences, eBooks and weekly news periodical Chemical & Engineering News. ACS journals are among the most cited, most trusted and most read within the scientific literature; however, ACS itself does not conduct chemical research. As a specialist in scientific information solutions (including SciFinder® and STN®), its CAS division powers global research, discovery and innovation. ACS' main offices are in Washington, D.C., and Columbus, Ohio.

ACS encourages journalists to apply for press credentials for the ACS Fall 2020 Virtual Meeting & Expo by contacting

To automatically receive news releases from the American Chemical Society, contact

Follow us: Twitter | Facebook

American Chemical Society

Related Iron Articles from Brightsurf:

How stony-iron meteorites form
Meteorites give us insight into the early development of the solar system.

Bouillon fortified with a new iron compound could help reduce iron deficiency
Iron fortification of food is a cost-effective method of preventing iron deficiency.

Iron nanorobots go undercover
Customizable magnetic iron nanowires pinpoint and track the movements of target cells.

Iron deficiency in corals?
When iron is limited, the microalgae that live within coral cells change how they take in other trace metals, which could have cascading effects on vital biological functions and perhaps exacerbate the effects of climate change on corals.

Blocking the iron transport could stop tuberculosis
The bacteria that cause tuberculosis need iron to survive. Researchers at the University of Zurich have now solved the first detailed structure of the transport protein responsible for the iron supply.

Observed: An exoplanet where it rains iron
Nature magazine is publishing today a surprising study about the giant, ultra-hot planet WASP-76b in which researchers from the Instituto de Astrofísica de Canarias (IAC) have taken part.

An iron-clad asteroid
Mineralogists from Jena and Japan discover a previously unknown phenomenon in soil samples from the asteroid 'Itokawa': the surface of the celestial body is covered with tiny hair-shaped iron crystals.

It's Iron, Man: ITMO scientists found a way to treat cancer with iron oxide nanoparticles
Particles previously loaded with the antitumor drug are injected in vivo and further accumulate at the tumor areas.

The brain may need iron for healthy cognitive development
Iron levels in brain tissue rise during development and are correlated with cognitive abilities, according to research in children and young adults recently published in JNeurosci.

The regulators active during iron deficiency
Iron deficiency is a critical situation for plants, which respond using specific genetic programmes.

Read More: Iron News and Iron Current Events is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to