Please select your home edition
Grapefruit Graphics 2019 - Leaderboard

WHOI engineered DISCO allows scientists to measure highly reactive superoxide on coral reefs

by The Woods Hole Oceanographic Institution 13 Dec 2019 15:27 UTC
MIT-WHOI Joint Program student Kalina Grabb demos the latest iteration of DISCO in a Watson lab at WHOI. © Daniel Hentz, Woods Hole Oceanographic Institution

Researchers at Woods Hole Oceanographic Institution (WHOI) successfully conceived and tested a portable device, DISCO, that performed the first in situ measurements of a highly reactive type of oxygen, known as superoxide, which may play an integral role in the health of coral reefs. Their findings were published as an early view article on Oct. 29 in the journal of Environmental Science and Technology.

Superoxide is a reactive chemical that is a byproduct within all respiring and photosynthesizing organisms. This unstable form of oxygen, or reactive oxygen species (ROS), is prone to stealing or giving electrons. As a consequence, superoxide has been known to catalyze chemical reactions that can lead to cancer and other diseases--one of the many reasons today's diets stress incorporating antioxidant-rich foods, such as blueberries, nuts or dark chocolate. However, in many organisms, including corals, the nature of superoxide may be more complicated.

"It used to be that [superoxide] was only considered toxic," says WHOI marine chemist Colleen Hansel, a coauthor of the study. "But we know now that it's used for a lot of beneficial processes... In fungi, plants and even animals, superoxide is important for an organism's immune response [for example]. That [logic] hasn't really transferred over into marine life yet."

Hansel and her team investigated the chemical's interaction with symbiotic microorganisms that inhabit coral reefs. Preliminary evidence suggests that while corals may not be immune to superoxide's toxic effects when it reaches high concentrations inside their cells, they may also be employing the chemical outside their cells for beneifical reasons, such as a defense against marine infections--some of which may be spurred on by warmer ocean temperatures.

"Superoxide to organisms reflects like a kind of Goldilocks effect," says Kalina Grabb, the study's lead author and WHOI-MIT Joint Program student in Hansel's lab. "You don't want too much because it can lead to oxidative stress, but you don't want too little because it's essential for physiological functions."

Until recently, the ephemeral nature of superoxide has made it incredibly difficult to sample in the marine environment- the chemical only lasts mere minutes in seawater. This traditionally left no time to transfer water samples to a lab for adequate analysis. At the same time, other boat-borne systems were cumbersome to operate and could only be used in very select environments.

To overcome these limitations, WHOI engineer Jason Kapit and WHOI scientist Scott Wankel worked closely with Hansel and her lab to develop the world's first portable DIver-operated Submersible Chemiluminescent SensOr, or DISCO. With it, they were able to sample superoxide concentrations in real time during a 2017 research trip to Cuba's pristine reef system, Jardines de la Reina.

The boxy handheld device comprises a water-sealed battery and a tablet screen that scuba divers can operate at depth. Inside, fluidic pumps uptake the invisible chemical as corals produce it. DISCO then adds a chemical to the mixture that reacts with superoxide to create measurable light, read by an onboard sensor. Armed with these tools, DISCO detected notable differences in superoxide levels between species of corals in its first field test.

"Now, we want to be able to get at the why," adds Hansel. "Why are they purposely making superoxide and is this helping the coral or is it related to stress in some way?"

Since its inception, DISCO has been reengineered to become even more portable and lightweight. In 2018, Hansel, Wankel and Kapit collaborated on another iteration of the device, this time at roughly half the size and weight of its predecessor. The team has also adapted DISCO into a deep-sea version known as SOLARIS to accompany WHOI's human-occupied submersible, ALVIN. In October 2019, they were able to use SOLARIS to detect superoxide produced by corals at 1,300 meters deep (~4,200 feet) along the Davison Seamount off the coast of central California.

"We are already talking about what we can do next with this technology," says Hansel. "How can we build new sensors that incorporate other reactive oxygen species to fully understand their role in organismal health and ocean chemistry? I don't see an end in sight."

Also collaborating on the paper are Scott Wankel, Jason Kapit, Kevin Manganini and Amy Apprill of Woods Hole Oceanographic Institution, and Maickel Armenteros from Universidad de La Habana. The research was funded by Schmidt Marine Technology Partners (G-1801-57385; to CMH), the National Science Foundation Graduate Research Fellowship Program (to KCG), and the Dalio Foundation's Ocean Initiative (now 'OceanX') (to AA). The research was conducted in the Jardines de la Reina, Cuba, in accordance with the requirements of the Republic of Cuba, conducted under permits NV2370 and NV2568 issued by the Ministerio de Relaciones Exteriores (MINREX). This research was also conducted in accordance with a memorandum of understanding between the National Center of Protected Areas (CNAP) of the Ministry of Science, Technology and Environment (CITMA) in Cuba and the Woods Hole Oceanographic Institution in the USA.

For more information, please visit

Related Articles

Epic Arctic mission ends
The German icebreaker Polarstern returned to its home port The German icebreaker Polarstern returned to its home port Oct. 12, 2020, after being frozen near the top of the world for nearly a year. Posted on 17 Oct
Ocean acidification causing coral 'osteoporosis'
A global-scale investigation of coral CT scans could help to target protections for vulnerable reefs Scientists have long suspected that ocean acidification is affecting corals' ability to build their skeletons, but it has been challenging to isolate its effect from that of simultaneous warming ocean temperatures, which also influence coral growth. Posted on 29 Aug
Uncharted Waters
Our global ocean will change dramatically over the next few decades Our global ocean will change dramatically over the next few decades. What might it look like, and how will humans adapt? Posted on 19 Jul
The many lifetimes of plastics
How long plastics last in the environment? Many of us have seen informational posters at parks or aquariums specifying how long plastics bags, bottles, and other products last in the environment. Posted on 20 Jun
A win for both lobstermen and endangered whales
Fishing with less gear and a shorter season could make the U.S. lobster fishery more profitable A new study by researchers at Woods Hole Oceanographic Institution (WHOI) found that New England's historic lobster fishery may turn a higher profit by operating with less gear in the water and a shorter season. Posted on 31 May
What did scientists learn from deepwater horizon?
Major findings and technological advances Paper reviews major findings, technological advances that could help in next deep-sea spill. Ten years ago, a powerful explosion destroyed an oil rig in the Gulf of Mexico, killing 11 workers and injuring 17 others. Posted on 27 Apr
New study on rapidly changing Arctic Ocean
Shelf sediments, freshwater runoff from rivers brings more carbon, nutrients to North Pole A new study by researchers at WHOI and their international colleagues found that freshwater runoff from rivers and continental shelf sediments are bringing significant quantities of carbon and trace elements into parts of the Arctic Ocean. Posted on 10 Apr
Biological pump captures more carbon than expected
Ocean plays an essential role in capturing carbon from the atmosphere Every spring in the Northern Hemisphere, the ocean surface erupts in a massive bloom of phytoplankton. Like plants, these single-celled floating organisms use photosynthesis to turn light into energy, consuming carbon dioxide and releasing oxygen Posted on 9 Apr
For now, river deltas gain land worldwide
Delta areas worldwide have actually gained land in the past 30 years Researchers from Utrecht University in the Netherlands, Woods Hole Oceanographic Institution (WHOI), and colleagues found that delta areas worldwide have actually gained land in the past 30 years, despite river damming. Posted on 26 Jan
How microbes reflect the health of coral reefs
Microorganisms play important roles in the health and protection of coral reefs Microorganisms play important roles in the health and protection of coral reefs, yet exploring these connections can be difficult due to the lack of unspoiled reef systems throughout the global ocean. Posted on 22 Dec 2019
Highfield Boats - Sailing - FOOTERUpffront 2020 Foredeck Club SW FOOTERCruise Village 2020 - FOOTER