Geoscientists unearth mineral-making secrets potentially useful for new technologies

August 01, 2013

Sugars are widely known as important sources of energy for all organisms.

Now, Virginia Tech researchers have discovered that certain types of sugars, known as polysaccharides, may also control the timing and placement of minerals that animals use to produce hard structures such as shells and exoskeletons of mollusks, lobsters, and shrimp.

Writing in the Proceedings of the National Academy of Sciences, Anthony Giuffre, a graduate student in the Department of Geosciences, and his research advisor, Patricia Dove, a University Distinguished Professor in the College of Science , propose a theory of how charged and uncharged sugars can be used to create shells and skeletons.

"Nature had 500 million years to become an amazing materials chemist," said Dove, the C.P. Miles Professor of Geosciences. "Here we are working in the most recent seconds of geologic time to harness those abilities. We can put that knowledge to work for new environmental, medical, and materials-based technologies, such as the developing new synthetic materials for bone repairs or tissue implants."

Proteins have gotten most of the attention in studies of how organic materials control the initial step of making the first tiny crystals that organisms use to build structures that help them move and protect themselves. This process of mineral nucleation is similar to how a pearl or a raindrop forms around a single speck, or nucleus.

"The old picture of divisions between the roles of proteins and polysaccharides melt away when one realizes the underlying chemical controls," Dove said. "In our efforts to establish a physical basis for how macromolecule chemistry controls biomineral nucleation, we are slowly deciphering nature's playbook of how to make these elaborate mineral structures in the laboratory."

The researchers discovered that organic molecules affect mineral formation as a continuum of energetic interactions governed by acidic and neutral chemical domains, the researchers said.

"Each type of polysaccharide is slightly different and provides a substrate that can tune the energy barrier for the calcium and carbonate ions to nucleate and begin building a bone or a shell," Giuffre said. "The same process is important in the life cycles of many different freshwater and marine organisms, including the microscopic plankton that support the food chain. Also, today's ocean has the correct recipe for the formation of biominerals, but we know the ocean's chemistry is changing. By learning the mechanisms of biomineralization, we can predict how organisms will respond to these changes."

The work, supported by the U.S. Department of Energy and the National Science Foundation, is a great example of the value of pursuing fundamental science research, Dove said. If researchers tie patterns of skeletal formation to specific types of molecules, it may also be possible to understand if and why organisms have changed in the fossil record.

In the meantime, the study reveals intricacies of a mineral-making process that is uniquely complex, but achievable by the simplest of organisms.

"People have always wondered, 'How does a biomineral start, and where does a biomineral actually form?'" said Clara Chan, an assistant professor of geological sciences at the University of Delaware College of Earth, Ocean, and Environment, who was not involved in the study. "Microorganisms need to collect the building blocks, then, they need a place to build the biomineral. This research says the biomineral is likely to form on a near neutral polysaccharide, which is like a gel. It makes sense that this would happen where the energy of the mineral, polysaccharide, and water is minimized -- this is a sophisticated system that goes far beyond gathering raw material and dumping it into a mineral. It is mind-boggling what these single-celled, basic microorganisms can do."
-end-


Virginia Tech

Related Organisms Articles from Brightsurf:

To push or to pull? How many-limbed marine organisms swim
Couinter-intuitively, small marine animals don't use their limbs or propulsors to push themselves through the water while swimming.

Identical evolution of isolated organisms
Palaeontologists at Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU) and the University of Calgary in Canada have provided new proof of parallel evolution: conodonts, early vertebrates from the Permian period, adapted to new habitats in almost identical ways despite living in different geographical regions.

The EU not ready for the release of Gene drive organisms into the environment
Gene drive organisms (GDOs) have been suggested as an approach to solve some of the most pressing environmental and public health issues.

Tiny marine organisms as the key to global cycles
Marine microorganisms play a very important role in global cycles such as of the uptake of carbon dioxide from the atmosphere.

Why organisms shrink
Everyone is talking about global warming. A team of paleontologists at GeoZentrum Nordbayern at Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU) has recently investigated how prehistoric organisms reacted to climate change, basing their research on belemnites.

The effects of microplastics on organisms in coastal areas
Microplastics (plastic particles under 5 mm) are an abundant type of debris found in salt and freshwater environments.

Climate change is reshaping communities of ocean organisms
Climate change is reshaping communities of fish and other sea life, according to a pioneering study on how ocean warming is affecting the mix of species.

Fungicides as an underestimated hazard for freshwater organisms
Large amounts of fungicides, used in agriculture, leak into nearby surface waters.

FEFU scientist reported on concentration of pesticides in marine organisms
According to ecotoxicologist from Far Eastern Federal University (FEFU), from the 90s and during 2000s in the tissues of Russian Far Eastern mussels the concentration of organochlorine pesticides (OCPs) that had been globally used in agriculture in the mid-twentieth century has increased about ten times.

How genes interact to build tissues and organisms
A group of scientists at the National Centre for Genomic Analysis (CNAG-CRG) from the Centre for Genomic Regulation (CRG), in Barcelona, Spain, led by Holger Heyn, developed a new computational tool, based on the mathematical Graph theory, to infer global, large-scale regulatory networks, from healthy and pathological organs, such as those affected by diabetes or Alzheimer's disease.

Read More: Organisms News and Organisms Current Events
Brightsurf.com 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 Amazon.com.