Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Microorganisms duke it out within algal blooms

01.03.2016

Looking closer, scientists discover that blooms such as 'red tides' encompass microscopic battles, with the front lines shifting on a daily basis

An unseen war rages between the ocean's tiniest organisms, and it has significant implications for understanding the ocean's role in climate change, according to a new study.


A fluorescence microscopic image showing an example of the phytoplankton and bacteria that David Needham and Jed Fuhrman observed during a five-month study of algal blooms. The large star-shape in the middle is phytoplankton; the larger green dots are bacteria or Archaea; and the tiny green dots are viruses.

Courtesy of David Needham and Jed Fuhrman/USC

David Needham and Jed Fuhrman from the USC Dornsife College of Letters, Arts and Sciences sampled water off the coast of Southern California over the course of five months, almost every day shortly after an algal bloom occurred, and found that the cloud of microorganisms is anything but uniform. Instead, they found traces of a constant battle between dozens of species, with the fortunes of war favoring different organisms on a daily basis.

Not only do the tiny organisms, known as phytoplankton, make up the base of the food chain in the ocean, they also are the planet's main scrubbers of carbon dioxide from the atmosphere.

"We witnessed a daily boom and bust among the phytoplankton species," said Fuhrman, senior author of a study that was published in Nature Microbiology on Feb. 29.

Scientists concerned with global warming have a vested interest in looking closely at phytoplankton. The microscopic plants, most of which are about as big as a piece of paper is thick, perform roughly half of the world's carbon fixation - that is, they convert carbon dioxide from the atmosphere into organic compounds that can be used by other organisms.

As creatures that exist on the boundary between sea and sky, they also have an outsized role in carbon fixation - sucking up atmospheric carbon dioxide and locking it away in the ocean.

Different phytoplankton manage carbon dioxide to varying degrees, however, making it important for researchers to gain a more nuanced understanding of algal blooms if they hope to quantify the blooms' role in carbon fixation and carbon sequestration.

Scientists have also long wondered about the trigger of algal blooms, which can include "red tides" caused by toxic dinoflagellates that poison marine life like sea lions and can render shellfish in the area unsafe to eat. Those dinoflagellates and other toxic algae were among some of the microorganisms that dominated the bloom periodically.

Most previous efforts to study the blooms relied on microscope analysis to classify which species of phytoplankton were in the mix - a problematic strategy, given that many of the organisms tend to look alike, even to a trained eye.

Instead, Needham and Fuhrman analyzed the organisms' ribosomal RNA, which give each species a distinctive and quantifiable signature. Specifically, they sequenced the RNA from the parts of the cell that perform photosynthesis, called chloroplasts.

"This could shift how this work is done in the future," said Needham, lead author of the study. "I think a lot of people are going to start taking a closer look at their blooms."

The samples were collected by dipping buckets off the side of the Miss Christi - the ship that sails daily between San Pedro and the USC Wrigley Marine Science Center (run by the USC Wrigley Institute for Environmental Studies) on Catalina Island - at a specific location at about the half way point of the trip each day.

The authors were surprised not only by the sheer diversity of phytoplankton in the bloom they studied - they counted about three dozen different species - but also by the constant and abrupt shifts in which species were dominant within the bloom.

Some of the species variability can be attributed to spatial variability However, the content of the samples changed too dramatically for that to be the sole cause, Needham and Fuhrman concluded.

In addition, as the phytoplankton varied, so did the species of bacteria and other microorganisms that feed on the organic material produced by them. On one of the sample days, the team was shocked to discover that the dominant species were in a group called the Archaea - single-celled microorganisms once thought to live only in extreme environments like hot springs.

"Until the 1990s nobody thought Archaea were even present in the sea in appreciable numbers," Needham said.

Needham and Fuhrman's findings also have bearing on the causes of algal blooms, which remain shrouded in mystery. Temperature and nutrient content of the ocean have been shown to help trigger the blooms - but they remain unpredictable.

###

This research was funded by the National Science Foundation, grants 1031743 and 1136818; and the Gordon and Betty Moore Foundation Marine Microbiology Initiative, grant GBMF3779.

The study can be found online at http://www.nature.com/articles/nmicrobiol20165.

Media Contact

Robert Perkins
perkinsr@usc.edu
213-740-9226

 @USC

http://www.usc.edu 

Robert Perkins | EurekAlert!

Further reports about: Marine algal blooms carbon dioxide carbon fixation dioxide microorganisms

More articles from Life Sciences:

nachricht Zap! Graphene is bad news for bacteria
23.05.2017 | Rice University

nachricht Discovery of an alga's 'dictionary of genes' could lead to advances in biofuels, medicine
23.05.2017 | University of California - Los Angeles

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Turmoil in sluggish electrons’ existence

An international team of physicists has monitored the scattering behaviour of electrons in a non-conducting material in real-time. Their insights could be beneficial for radiotherapy.

We can refer to electrons in non-conducting materials as ‘sluggish’. Typically, they remain fixed in a location, deep inside an atomic composite. It is hence...

Im Focus: Wafer-thin Magnetic Materials Developed for Future Quantum Technologies

Two-dimensional magnetic structures are regarded as a promising material for new types of data storage, since the magnetic properties of individual molecular building blocks can be investigated and modified. For the first time, researchers have now produced a wafer-thin ferrimagnet, in which molecules with different magnetic centers arrange themselves on a gold surface to form a checkerboard pattern. Scientists at the Swiss Nanoscience Institute at the University of Basel and the Paul Scherrer Institute published their findings in the journal Nature Communications.

Ferrimagnets are composed of two centers which are magnetized at different strengths and point in opposing directions. Two-dimensional, quasi-flat ferrimagnets...

Im Focus: World's thinnest hologram paves path to new 3-D world

Nano-hologram paves way for integration of 3-D holography into everyday electronics

An Australian-Chinese research team has created the world's thinnest hologram, paving the way towards the integration of 3D holography into everyday...

Im Focus: Using graphene to create quantum bits

In the race to produce a quantum computer, a number of projects are seeking a way to create quantum bits -- or qubits -- that are stable, meaning they are not much affected by changes in their environment. This normally needs highly nonlinear non-dissipative elements capable of functioning at very low temperatures.

In pursuit of this goal, researchers at EPFL's Laboratory of Photonics and Quantum Measurements LPQM (STI/SB), have investigated a nonlinear graphene-based...

Im Focus: Bacteria harness the lotus effect to protect themselves

Biofilms: Researchers find the causes of water-repelling properties

Dental plaque and the viscous brown slime in drainpipes are two familiar examples of bacterial biofilms. Removing such bacterial depositions from surfaces is...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

AWK Aachen Machine Tool Colloquium 2017: Internet of Production for Agile Enterprises

23.05.2017 | Event News

Dortmund MST Conference presents Individualized Healthcare Solutions with micro and nanotechnology

22.05.2017 | Event News

Innovation 4.0: Shaping a humane fourth industrial revolution

17.05.2017 | Event News

 
Latest News

Scientists propose synestia, a new type of planetary object

23.05.2017 | Physics and Astronomy

Zap! Graphene is bad news for bacteria

23.05.2017 | Life Sciences

Medical gamma-ray camera is now palm-sized

23.05.2017 | Medical Engineering

VideoLinks
B2B-VideoLinks
More VideoLinks >>>