Featured Research

from universities, journals, and other organizations

Cracking the blue-green code: Study of gene expression in blue-green algae reveals what makes it bloom, toxic

Date:
July 24, 2013
Source:
Stony Brook University
Summary:
If your local pond, lake, or watering hole is looking bright green this summer, chances are it has blue-green algae and it may be dangerous to you or your pets. A newly published study has used a novel approach to better understand why these algae form blooms and what makes them toxic.

Blue-green algae blooms formed by Microcystis.
Credit: Christopher Gobler

Blue-green algae blooms formed by Microcystis (Credit: Christopher Gobler) If your local pond, lake, or watering hole is looking bright green this summer, chances are it has blue-green algae and it may be dangerous to you or your pets. A newly published study has used a novel approach to better understand why these algae form blooms and what makes them toxic.

Matthew Harke and Christopher Gobler of Stony Brook University's School of Marine and Atmospheric Sciences, used global gene expression analysis of the most common blue-green algae, Microcystis, to uncover how it uses different types of nutrients to form blooms and what regulates the production of its toxin, microcystin. The study, entitled "Global transcriptional responses of the toxic cyanobacterium, Microcystis aeruginosa, to nitrogen stress, phosphorus stress, and growth on organic matter," published in the July 23rd edition of the journal PLoS ONE, is the first to use this approach with this algae.

"Toxic blue-green algae blooms are a common phenomenon in freshwater lakes and ponds, particularly during summer and early fall," says Dr. Gobler. "These algae can create various toxins that can harm humans, pets, and aquatic life."

And the problem is worsening. "The distribution, frequency and intensity of these events have increased across the globe and in the US in places like the Great Lakes and scientists have been struggling to determine why this is happening," notes Gobler.

Individual algae cells so tiny -- 50 of them side by side span only the width of a single hair -- that they may seem harmless. But when billions of blue green algae come together, they can be dangerous to humans and damaging to aquatic life. Human exposure to blue-green algal toxins can be through drinking water supply or direct contact with blooms via recreation.

This study grew the toxic blue-green algae known as Microcystis with high and low levels of different sources of nutrients such as nitrogen and phosphorus and used high-throughput sequencing of its transcriptome to simultaneously evaluate the expression of all 6,300 of the genes in its genome. In doing so, the study revealed the sets of genes it uses to sustain blooms, specifically during summer when some types of nutrients can be in short supply, and yet Microcystis still grows quickly.

"This algae has a series of 'gene pathways' it can turn on to continue to grow rapidly, even as environmental conditions change," said first author and doctoral student Matthew Harke. "We think this ability to quickly turn on and off different genes to grow when nitrogen or phosphorus levels are high or low and to use organic or inorganic nutrients may be a key to its success."

An additional striking finding in the study was the ability of nitrogen to alter the toxicity of Microcystis. Scientists have long debated the relative importance of nitrogen and phosphorus in controlling blue-green algae blooms. "By examining all of the genes responsible for synthesizing the microcystin toxin, we were specifically able to see that these genes were turned off when the nitrogen supply of Microcystis ran out and that the cells contained less toxin," said senior author, Dr. Christopher Gobler.

The findings of the study lend support to the notion that limiting nutrient input into lakes will restrict the intensity of blue-green algae blooms. The findings also demonstrated that lessening the input of both nitrogen and phosphorus may be needed to reduce the density and toxicity of these events.


Story Source:

The above story is based on materials provided by Stony Brook University. Note: Materials may be edited for content and length.


Journal Reference:

  1. Matthew J. Harke, Christopher J. Gobler. Global Transcriptional Responses of the Toxic Cyanobacterium, Microcystis aeruginosa, to Nitrogen Stress, Phosphorus Stress, and Growth on Organic Matter. PLoS ONE, 2013; 8 (7): e69834 DOI: 10.1371/journal.pone.0069834

Cite This Page:

Stony Brook University. "Cracking the blue-green code: Study of gene expression in blue-green algae reveals what makes it bloom, toxic." ScienceDaily. ScienceDaily, 24 July 2013. <www.sciencedaily.com/releases/2013/07/130724101549.htm>.
Stony Brook University. (2013, July 24). Cracking the blue-green code: Study of gene expression in blue-green algae reveals what makes it bloom, toxic. ScienceDaily. Retrieved April 16, 2014 from www.sciencedaily.com/releases/2013/07/130724101549.htm
Stony Brook University. "Cracking the blue-green code: Study of gene expression in blue-green algae reveals what makes it bloom, toxic." ScienceDaily. www.sciencedaily.com/releases/2013/07/130724101549.htm (accessed April 16, 2014).

Share This



More Plants & Animals News

Wednesday, April 16, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Ebola Outbreak Now Linked To 121 Deaths

Ebola Outbreak Now Linked To 121 Deaths

Newsy (Apr. 15, 2014) The ebola virus outbreak in West Africa is now linked to 121 deaths. Health officials fear the virus will continue to spread in urban areas. Video provided by Newsy
Powered by NewsLook.com
In Washington, a Push to Sterilize Stray Cats

In Washington, a Push to Sterilize Stray Cats

AFP (Apr. 14, 2014) To curb the growing numbers of feral cats in the US capital, the Washington Humane Society is encouraging residents to set traps and bring the animals to a sterilization clinic, after which they are released.. Duration: 02:29 Video provided by AFP
Powered by NewsLook.com
After Attack, Officials Kill 5 Bears in Florida

After Attack, Officials Kill 5 Bears in Florida

AP (Apr. 14, 2014) Florida wildlife officials say they have killed five bears following an attack on a woman in a suburban subdivision in central Florida. Forty-five year-old Terri Frana was attacked by a large bear in her driveway Saturday. (April 14) Video provided by AP
Powered by NewsLook.com
Uruguay Opens Its First Cannabis Library

Uruguay Opens Its First Cannabis Library

AFP (Apr. 13, 2014) Uruguay opened its first Cannabis Library in Montevideo on Saturday, where people can come and read books on cannabis or take classes on how to grow the plant or even how to cook with it. Duration: 01:20 Video provided by AFP
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins