Featured Research

from universities, journals, and other organizations

"Grow-In-The-Dark" Algae May Promise Dietary Supplements, Glowing Pigments, And More, Say Science Authors

Date:
June 15, 2001
Source:
American Association For The Advancement Of Science
Summary:
By tinkering with a single gene, researchers have weaned photosynthetic algae off their dependence on sunlight and engineered them to grow and thrive in darkness. This accomplishment, reported in the 15 June issue of the journal Science, could pave the way towards clean, efficient, and inexpensive production of microalgae, which are used in a variety of commercial applications.

By tinkering with a single gene, researchers have weaned photosynthetic algae off their dependence on sunlight and engineered them to grow and thrive in darkness. This accomplishment, reported in the 15 June issue of the journal Science, could pave the way towards clean, efficient, and inexpensive production of microalgae, which are used in a variety of commercial applications.

Common microalgae products include fluorescent pigments used in scientific labeling, dietary supplements such as beta-carotene and the fatty acid DHA, which is essential for nervous system development in infants, and feed for farm-raised fish, shrimp, and other aquaculture products.

Since these single-celled aquatic plants depend on sunlight for their energy, they are typically commercially cultivated in large outdoor ponds. These pond "farms" have several drawbacks, however, that make it difficult to control the quality and quantity of their microalgae produce. Contaminants can invade the pond, daily and seasonal changes in light and temperature can make growth rates unpredictable, and the algae can shade each other after a certain point, restricting the available light.

To solve these problems, commercial producers would like to grow microalgae inside fermenters where the tiny plants could be monitored for maximum purity and productivity. This technique requires that the algae give up their photosynthetic ways and use glucose (or another carbon compound) as their primary energy source.

Since most microalgae are unable to make this switch on their own, the Science researchers gave the microalgae Phaeodactylum tricornutum a metabolic boost by introducing a gene that encodes a glucose transporter. The researchers experimented with a variety of glucose transporter genes from human red blood cells, a different microalgae species, and yeast to determine which transporter type might allow the algae to increase its rates of glucose uptake.

P. tricornutum cells transformed with either the human or microalgal glucose transporter gene increased their rates of glucose uptake over normal cells, while the yeast genes produced no detectable difference in glucose uptake. Unlike normal P. tricornutum, the engineered algae expressing the human transporter were able to grow in darkened fermenters at densities fifteen times that of sunlight-grown algae.

Along with increased yield, the engineered algae grown in the fermenters have another distinct advantage--protection from microbial contamination. "Eliminating contamination means that the algae can be produced at a high purity for pharmaceutical applications or dietary supplements," says Science co-author Kirk E.Apt of Martek Biosciences Corporation.

The Science authors say that their research "demonstrates that a fundamental change in the metabolism of an organism can be accomplished through the introduction of a single gene." They acknowledge, however, that a one-gene solution will probably be the exception and not the rule for future metabolic engineering projects. In the case of P. tricornutum, for instance, the researchers found that the complete cellular pathway for breaking down glucose was "preinstalled" in the microalgae, and the additional gene simply allowed the plant to take advantage of its own systems.

In a related article in Science, Gregory Stephanopoulos of Massachusetts Institute of Technology and Joanne Kelleher of George Washington University School of Medicine suggest that metabolic engineering is moving away from single gene modifications and towards alteration of several targets within a particular pathway. "My own suspicion is that it won't always be this simple," says Apt. On the heels of their success with P. tricornutum, however, the research team is already developing other commercially important microalgae that can be grown using fermenter technology.

The other members of the research team include L.A. Zaslavskaia and J.C. Lippmeier at Martek Biosciences Corporation, and C. Shih, D. Ehrhardt, and A.R. Grossman at Carnegie Institute of Washington. This research was supported in part by NSF and the Carnegie Institute of Washington.


Story Source:

The above story is based on materials provided by American Association For The Advancement Of Science. Note: Materials may be edited for content and length.


Cite This Page:

American Association For The Advancement Of Science. ""Grow-In-The-Dark" Algae May Promise Dietary Supplements, Glowing Pigments, And More, Say Science Authors." ScienceDaily. ScienceDaily, 15 June 2001. <www.sciencedaily.com/releases/2001/06/010615072508.htm>.
American Association For The Advancement Of Science. (2001, June 15). "Grow-In-The-Dark" Algae May Promise Dietary Supplements, Glowing Pigments, And More, Say Science Authors. ScienceDaily. Retrieved July 25, 2014 from www.sciencedaily.com/releases/2001/06/010615072508.htm
American Association For The Advancement Of Science. ""Grow-In-The-Dark" Algae May Promise Dietary Supplements, Glowing Pigments, And More, Say Science Authors." ScienceDaily. www.sciencedaily.com/releases/2001/06/010615072508.htm (accessed July 25, 2014).

Share This




More Plants & Animals News

Friday, July 25, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Boy Attacked by Shark in Florida

Boy Attacked by Shark in Florida

Reuters - US Online Video (July 24, 2014) An 8-year-old boy is bitten in the leg by a shark while vacationing at a Florida beach. Linda So reports. Video provided by Reuters
Powered by NewsLook.com
Goma Cheese Brings Whiff of New Hope to DRC

Goma Cheese Brings Whiff of New Hope to DRC

Reuters - Business Video Online (July 24, 2014) The eastern region of the Democratic Republic of Congo, mainly known for conflict and instability, is an unlikely place for the production of fine cheese. But a farm in the village of Masisi, in North Kivu is slowly transforming perceptions of the area. Known simply as Goma cheese, the Congolese version of Dutch gouda has gained popularity through out the region. Ciara Sutton reports. Video provided by Reuters
Powered by NewsLook.com
Tyrannosaur Pack-Hunting Theory Aided By New Footprints

Tyrannosaur Pack-Hunting Theory Aided By New Footprints

Newsy (July 24, 2014) A new study claims a set of prehistoric T-Rex footprints supports the theory that the giant predators hunted in packs instead of alone. Video provided by Newsy
Powered by NewsLook.com
Dogs Appear To Become Jealous Of Owners' Attention

Dogs Appear To Become Jealous Of Owners' Attention

Newsy (July 23, 2014) A U.C. San Diego researcher says jealousy isn't just a human trait, and dogs aren't the best at sharing the attention of humans with other dogs. Video provided by Newsy
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