Microscopic chalk discs in oceans play a key role in earth's carbon
cycle by propagating viruses
Rutgers-led research finds biomineral structures formed by marine algae
foment viral infection, contributing positively to capture CO2

Date:
March 6, 2023
Source:
Rutgers University
Summary:
A team of scientists studying virus-host interactions of a
globally abundant, armor-plated marine algae, Emiliania huxleyi,
has found that the circular, chalk plates the algae produce can
act as catalysts for viral infection, which has vast consequences
for trillions of microscopic oceanic creatures and the global
carbon cycle.


Facebook Twitter Pinterest LinkedIN Email
FULL STORY ==========================================================================
A Rutgers-led team of scientists studying virus-host interactions of
a globally abundant, armor-plated marine algae, Emiliania huxleyi,
has found that the circular, chalk plates the algae produce can act as catalysts for viral infection, which has vast consequences for trillions
of microscopic oceanic creatures and the global carbon cycle.


==========================================================================
"In a drop of seawater, there will be about 1,000 to 10,000
E. huxleyicells, and about 10 million viruses," said Kay Bidle, a
professor in the Department of Marine and Coastal Sciences at Rutgers
School of Environmental and Biological Sciences (SEBS) and a senior
author on the study. "They're all in a sort of arms race against
each other and we are studying it to see how it plays out and impacts
Earth's carbon cycle." Reporting in Science Advances, the researchers
said they discovered, through observations both in the ocean and in the laboratory, that the chalk (calcium carbonate) plates, called coccoliths,
are a previously unrealized central player in viral infections that can collapse phytoplankton blooms the size of some countries within weeks.

"Coccoliths can act as catalysts for death, delivering viruses directly
to algae cells for successful infection," said Christopher Johns, a
doctoral student in the Department of Marine and Coastal Sciences at
SEBS and lead author on the study.

E. huxleyiis a one-celled species of phytoplankton, which, like trees,
performs photosynthesis. In the case of phytoplankton, they convert
carbon dioxide dissolved in ocean water into organic compounds, and at
the same time produce oxygen.

"The phytoplankton in the oceans contribute about half of Earth's oxygen,
with the other half coming from land plants," Bidle said. "Every other
breath you take is from phytoplankton." E. huxleyiis well-known for
its ability to biomineralize calcium carbonate, similar to corals, by
producing coccoliths, which are arranged on the cell surface to form
an armored layer. These coccoliths are produced and then shed into the surrounding seawater in a continuous cycle.

For years, the function of these coccoliths has been poorly understood, according to Bidle. Researchers believed the chalk armor existed in
part to protect phytoplankton from getting infected by viruses. And the discarded, free coccoliths were commonly thought of as passively drifting planktonic particles with little biological or ecological roles.

But in experiments conducted in laboratories on the Cook campus at Rutgers University-New Brunswick, Johns and other team members observed that
the expelled coccoliths can find their way back to the E. huxleyicells, reattach, and at the same time ferry viral particles, facilitating
infection. This ability to propagate and catalyze infection is one
unexpected role of the coccoliths with important potential ecosystem
outcomes.

The discovery also has an important connection to climate change and
the Earth's carbon cycle, Bidle said. Infected E. huxleyicells produce
a sticky glue that can help aggregate particles into what is called
"marine snow." When marine snow sinks to the deep ocean, it helps to
sequester and bury carbon, removing it from the atmosphere for centuries
to millennia. Coccoliths are important in this process because they
are heavier than seawater and help make particles sink faster and more
rapidly into the deep ocean.

By assisting in the death of the phytoplankton, as well as in marine
snow formation and sinking, the coccolith biominerals can ultimately
have a positive impact on the removal of carbon dioxide from the upper
ocean and atmosphere, Bidle said.

"This means the coccoliths facilitate the process of sequestering or
sinking carbon into the deep ocean for thousands of years, making them important players in balancing the Earth's carbon cycle," Bidle said.

Other Rutgers researchers on the study include Associate Professor
Heidi Fuchs; Karen Grace Bondoc-Naumovitz, a former postdoctoral fellow
now at the University of Exeter in England; and Alexandra Matthews,
a former undergraduate student, all within the Department of Marine and
Coastal Sciences.

Researchers from the U.S. Department of Energy's Oak Ridge National
Laboratory, the University of California-Santa Barbara, and the University
of North Carolina-Wilmington also were involved in the study.

* RELATED_TOPICS
o Health_&_Medicine
# Viruses # HIV_and_AIDS # Infectious_Diseases
# Healthy_Aging # STD # Medical_Topics #
Diseases_and_Conditions # Vegetarian
* RELATED_TERMS
o Seaweed o Red_tide o Natural_killer_cell o H5N1 o
Microorganism o Encephalitis o West_Nile_virus o Wart

========================================================================== Story Source: Materials provided by Rutgers_University. Original written
by Kitta MacPherson.

Note: Content may be edited for style and length.


========================================================================== Journal Reference:
1. Christopher T. Johns, Karen Grace Bondoc-Naumovitz, Alexandra
Matthews,
Paul G. Matson, M. Debora Iglesias-Rodriguez, Alison R. Taylor,
Heidi L.

Fuchs, Kay D. Bidle. Adsorptive exchange of coccolith biominerals
facilitates viral infection. Science Advances, 2023; 9 (3) DOI:
10.1126/ sciadv.adc8728 ==========================================================================

Link to news story: https://www.sciencedaily.com/releases/2023/03/230306143506.htm

--- up 1 year, 1 week, 10 hours, 50 minutes
* Origin: -=> Castle Rock BBS <=- Now Husky HPT Powered! (1:317/3)