Without Sunlight

Scientists Alter Algae to Grow Without Sunlight
Reuters, June 14, 2001

Scientists said on Thursday they had genetically engineered a type of algae to grow without sunlight, a breakthrough that could cut the cost of growing the single-celled plant used in dietary supplements. The addition of a single gene caused the algae to give up sunlight as its primary energy source - a process known as photosynthesis - and use glucose, a sugar, instead, researchers said in a study appearing in the journal Science. Commercial cultivation of algae is typically done in large outdoor ponds, where contamination by microbes and variations in sunlight and temperature can reduce the quality and quantity of the plants, the scientists said. “Eliminating contamination means that the algae can be produced at a high purity for pharmaceutical applications or dietary supplements,” said study co-author Kirk Apt of Martek Biosciences Corp. In addition to dietary supplements such as beta-carotene and the fatty acid DHA, algae is used in fluorescent pigments for scientific labeling and in food for commercial fish farms.

The scientists said they also found that the gene-altered algae grew at 15 times the density of sunlight-grown algae, partly because the algae in outdoor ponds can shade each other, restricting the available light. To get the algae called Phaeodactylum tricornutum to feed off glucose or another carbon compound instead of sunlight, a single gene from either human red blood cells or another type of algae was inserted, they said. These so-called glucose transporter genes changed the metabolism of the algae into glucose eaters, allowing them to grow in darkness. The scientists said future efforts to change the metabolism of plants through genetic engineering likely would be more complicated than just adding a single gene. P. tricornutum was primed for the change because it has the complete cellular pathway for breaking down glucose ''preinstalled'' and the additional gene simply allowed the plant to take advantage of its own biology, they said.

This algae without light seems like a great idea, but I have a feeling it's coming to late, meaning how quick will it make to any kind of marketplace. This is an engineered organism so I don't thinks we'll see it any time soon. Also, trying to grow one type of organism is always a challenge. Keeping competitors out would be tough, especially post pole shift. I think we are better of trying yeast, it essentially does the same think (eats sugar without needing light). But if we have sugar why wouldn't we just eat it ourselves. In my opinion we should concentrate on algae, provided we can supply the light. We can feed it to our ducks, chickens, fish etc.

Offered by Stan.