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 Single-stranded DNA and RNA origami go live
15.12.2017 | Wyss Institute for Biologically Inspired Engineering at Harvard

nachricht New antbird species discovered in Peru by LSU ornithologists
15.12.2017 | Louisiana State University

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: First-of-its-kind chemical oscillator offers new level of molecular control

DNA molecules that follow specific instructions could offer more precise molecular control of synthetic chemical systems, a discovery that opens the door for engineers to create molecular machines with new and complex behaviors.

Researchers have created chemical amplifiers and a chemical oscillator using a systematic method that has the potential to embed sophisticated circuit...

Im Focus: Long-lived storage of a photonic qubit for worldwide teleportation

MPQ scientists achieve long storage times for photonic quantum bits which break the lower bound for direct teleportation in a global quantum network.

Concerning the development of quantum memories for the realization of global quantum networks, scientists of the Quantum Dynamics Division led by Professor...

Im Focus: Electromagnetic water cloak eliminates drag and wake

Detailed calculations show water cloaks are feasible with today's technology

Researchers have developed a water cloaking concept based on electromagnetic forces that could eliminate an object's wake, greatly reducing its drag while...

Im Focus: Scientists channel graphene to understand filtration and ion transport into cells

Tiny pores at a cell's entryway act as miniature bouncers, letting in some electrically charged atoms--ions--but blocking others. Operating as exquisitely sensitive filters, these "ion channels" play a critical role in biological functions such as muscle contraction and the firing of brain cells.

To rapidly transport the right ions through the cell membrane, the tiny channels rely on a complex interplay between the ions and surrounding molecules,...

Im Focus: Towards data storage at the single molecule level

The miniaturization of the current technology of storage media is hindered by fundamental limits of quantum mechanics. A new approach consists in using so-called spin-crossover molecules as the smallest possible storage unit. Similar to normal hard drives, these special molecules can save information via their magnetic state. A research team from Kiel University has now managed to successfully place a new class of spin-crossover molecules onto a surface and to improve the molecule’s storage capacity. The storage density of conventional hard drives could therefore theoretically be increased by more than one hundred fold. The study has been published in the scientific journal Nano Letters.

Over the past few years, the building blocks of storage media have gotten ever smaller. But further miniaturization of the current technology is hindered by...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

See, understand and experience the work of the future

11.12.2017 | Event News

Innovative strategies to tackle parasitic worms

08.12.2017 | Event News

AKL’18: The opportunities and challenges of digitalization in the laser industry

07.12.2017 | Event News

 
Latest News

Engineers program tiny robots to move, think like insects

15.12.2017 | Power and Electrical Engineering

One in 5 materials chemistry papers may be wrong, study suggests

15.12.2017 | Materials Sciences

New antbird species discovered in Peru by LSU ornithologists

15.12.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>