Corporate Banner
Satellite Banner
AgriGenomics
Scientific Community
 
Become a Member | Sign in
Home>News>This Article
  News
Return

Biologists Engineer Algae to Make Complex Anti-Cancer ‘Designer’ Drug

Published: Thursday, December 13, 2012
Last Updated: Thursday, December 13, 2012
Bookmark and Share
Biologists at UC San Diego have succeeded in genetically engineering algae to produce a complex and expensive human therapeutic drug used to treat cancer.

Their achievement, detailed in a paper in this week’s early online issue of The Proceedings of the National Academy of Sciences, opens the door for making these and other “designer” proteins in larger quantities and much more cheaply than can now be made from mammalian cells.

“Because we can make the exact same drug in algae, we have the opportunity to drive down the price down dramatically,” said Stephen Mayfield, a professor of biology at UC San Diego and director of the San Diego Center for Algae Biotechnology or SD-CAB, a consortium of research institutions that is also working to develop new biofuels from algae.

Their method could even be used to make novel complex designer drugs that can’t be produced in any other systems--drugs that could be used to treat cancer or other human diseases in new ways.

“You can’t make these drugs in bacteria, because bacteria are incapable of folding these proteins into these complex, three-dimensional shapes,” said Mayfield. “And you can’t make these proteins in mammalian cells because the toxin would kill them.”

The advance is the culmination of seven years of work in Mayfield’s laboratory to demonstrate that Chlamydomonas reinhardtii, a green alga used widely in biology laboratories as a genetic model organism can produce a wide range of human therapeutic proteins in greater quantity and more cheaply than bacteria or mammalian cells.

Mayfield and his colleagues achieved their first breakthrough five years ago when they demonstrated they could produce a mammalian serum amyloid protein in algae. The following year, they succeeded in getting algae to produce a human antibody protein. In 2010, they demonstrated that more complex proteins—human therapeutic drugs, such as human vascular endothelial growth factor, or VEGF, used to treat patients suffering from pulmonary emphysema—could be produced in algae.

Then in May of this year, Mayfield’s group working with another team headed by Joseph Vinetz from UC San Diego’s School of Medicine, engineered algae to produce an even more complex protein—a new kind of vaccine that, preliminary experiments suggest, could protect billions of people from malaria, one of the world’s most prevalent and debilitating diseases.

“What the development of the malarial vaccine showed us was that algae could produce proteins that were really complex structures, containing lots of disulfide bonds that would still fold into the correct three-dimensional structures,” said Mayfield. “Antibodies were the first sophisticated proteins we made. But the malarial vaccine is complex, with disulfide bonds that are pretty unusual. So once we made that, we were convinced we could make just about anything in algae.”

In their latest development, the scientists genetically engineered algae to produce a complex, three-dimensional protein with two “domains”—one of which contains an antibody, which can home in on and attach to a cancer cell and another domain that contains a toxin that kills the bound cancer cells. Such “fusion proteins” are presently created by pharmaceutical companies in a complex, two-step process by first developing the antibody domain in a Chinese hamster, or CHO, cell. The antibody is purified, then chemically attached to a toxin outside of the cell. Then the final protein is re-purified.

“We have a two-fold advantage over that process,” said Mayfield. “First, we make this as a single protein with the antibody and toxin domains fused together in a single gene, so we only have to purify it one time. And second, because we make this in algae rather than CHO cells, we get an enormous cost advantage on the production of the protein.”

The fusion protein the researchers in his laboratory produced from algae is identical to one that is under development by pharmaceutical companies with a proposed cost of more than $100,000.  This same protein could be produced in algae for a fraction of that price, they report in their paper. And the UCSD researchers—Miller Tran, Christina Van, Dan Barrera and Jack Bui, at the UC San Diego Medical School—confirmed that the compound worked like the more expensive treatment: it homed in on cancer cells and inhibited the development of tumors in laboratory mice.

Mayfield said such a fusion protein could not have been produced in a mammalian CHO cell, because the toxin would have killed it. But because the protein was produced in the algae’s chloroplasts—the part of algal and plant cells where photosynthesis takes place—it did not kill the algae.

“The protein was sequestered inside the chloroplast,” Mayfield said. “And the chloroplast has different proteins from the rest of the cell, and these are not affected by the toxin. If the protein we made were to leak out of the chloroplast, it would have killed the cell. So it’s amazing to think that not one molecule leaked out of the chloroplasts. There are literally thousands of copies of that protein inside the chloroplasts and not one of them leaked out.”

Mayfield said producing this particular fusion protein was fairly straightforward because it involved fusing two domains—one to recognize and bind to cancer cells and another to kill them. But in the future, he suspects this same method could be used to engineer algae to produce more complex proteins with multiple domains.

“Can we string together four or five domains and produce a designer protein in algae with multiple functions that doesn’t exist in nature? I think we can?” he added. “Suppose I want to couple a receptor protein with a series of activator proteins so that I could stimulate bone production or the production of neurons? At some point you can start thinking about medicine the same way we think about assembling a computer, combining different modules with specific purposes. We can produce a protein that has one domain that targets the kind of cell you want to impact, and another domain that specifies what you want the cell to do.”


Further Information

Join For Free

Access to this exclusive content is for Technology Networks Premium members only.

Join Technology Networks Premium for free access to:

  • Exclusive articles
  • Presentations from international conferences
  • Over 2,900+ scientific posters on ePosters
  • More than 4,200+ scientific videos on LabTube
  • 35 community eNewsletters


Sign In



Forgotten your details? Click Here
If you are not a member you can join here

*Please note: By logging into TechnologyNetworks.com you agree to accept the use of cookies. To find out more about the cookies we use and how to delete them, see our privacy policy.

Related Content

Key Enzyme in Pierce’s Disease Grapevine Damage Uncovered
UC Davis plant scientists have identified an enzyme that appears to play a key role in the insect-transmitted bacterial infection of grapevines with Pierce’s disease, which annually costs California’s grape and wine industries more than $100 million.
Wednesday, January 13, 2016
Genome Sequencing May Save California's Legendary Sugar Pine
The genome of California’s legendary sugar pine, which naturalist John Muir declared to be “king of the conifers” more than a century ago, has been sequenced by a research team led by UC Davis scientists.
Thursday, December 17, 2015
UC Davis Cracks the Walnut Genome
Scientists at the University of California, Davis, have for the first time sequenced the genome of a commercial walnut variety.
Friday, December 11, 2015
New Organic Plant Breeding Effort Launched
A new effort to provide California growers with seeds for tomato, bean, pepper and other crop varieties that are specially bred for organic farming has been launched at UC Davis.
Tuesday, December 01, 2015
Crop Cure
Scientists in new center to use medical research techniques to help food crops withstand drought and climate change.
Friday, October 16, 2015
Sustaining Our Salad
Improving lettuce crops is the aim of a new, $4.5 million grant, awarded to University of California, Davis, researchers by the U.S. Department of Agriculture's National Institute of Food and Agriculture.
Thursday, October 15, 2015
Industry-Sponsored Academic Inventions Spur Increased Innovation
Analysis questions assumption that corporate support skews science toward inventions that are less useful than those funded by the government or non-profit organizations.
Monday, March 24, 2014
International Fruit Pest Targeted by Genomic Research
The spotted wing drosophila is itself being targeted, thanks to groundbreaking genome sequencing.
Friday, December 06, 2013
DNA Sequencing Lifts Veil on Wine’s Microbial Terroir
It’s widely accepted that terroir — the unique blend of a vineyard’s soils, water and climate — sculpts the flavor and quality of wine.
Wednesday, November 27, 2013
Grapevine Virus Screening Saves Napa-Sonoma $60M
Providing disease-free grapevines and rootstock to California’s famed North Coast wine region is money-wise to the tune of more than $60 million annually.
Tuesday, November 19, 2013
New Cattle Virus Identified by Genome Sequencing
A new cow virus that causes neurologic symptoms reminiscent of mad cow disease has been identified and its genome sequenced by a team of researchers.
Thursday, August 15, 2013
More Accurate Model of Climate Change’s Effect on Soil
Scientists have developed a new computer model to measure global warming's effect in soil worldwide that accounts for how bacteria and fungi in soil control carbon.
Friday, August 02, 2013
Predicting how Insects, Plants Interact
Butterfly and moth larvae feeding on native plants will extend their diet to newly introduced non-native plants, but which ones?
Tuesday, July 23, 2013
Gene Discovery May Halt Disease that Threatens Wheat
Researchers have identified a gene that enables resistance to a new race, or strain, of stem rust, a disease threatening global food security.
Monday, July 01, 2013
Reforms Could Boost Use of Land Conservation Banks
California legislators have enacted the state's first conservation banking law, based on a pioneering program launched 18 years ago.
Tuesday, June 11, 2013
Scientific News
Tick Genome Reveals Secrets of a Successful Bloodsucker
NIH-funded study could lead to new tick control methods.
New Method Promises to Speed Development of Food Crops
A new study addresses a central challenge of transgenic plant development: how to reliably evaluate whether genetic material has been successfully introduced.
Where Cancer Cells May Begin
Scientists use fruit fly genetics to understand how things could go wrong in cancer.
Key Enzyme in Pierce’s Disease Grapevine Damage Uncovered
UC Davis plant scientists have identified an enzyme that appears to play a key role in the insect-transmitted bacterial infection of grapevines with Pierce’s disease, which annually costs California’s grape and wine industries more than $100 million.
Bacteria Attack Lignin with Enzymatic Tag Team
Team from Rice, University of Wisconsin-Madison shows how nature handles lignin.
Milestone Resource in Wheat Research Now Available for Download
Leading on from The Genome Analysis Centre’s (TGAC) previous announcement of their new bread wheat genome assembly, the landmark resource is now publically available to download at the European Bioinformatics Institute’s (EMBL-EBI) Ensembl database for full analysis.
Nano-Reactor for the Production of Hydrogen Biofuel
Combining bacterial genes and virus shell creates a highly efficient, renewable material used in generating power from water.
Cleaning Wastewater with Pond Scum
A blob of algae scooped from a fountain on South Street almost two years ago, has seeded a crop of the green stuff that Drexel University researchers claim is more effective at treating wastewater than many of the processes employed in municipal facilities today.
Global Reductions in Mercury Emissions Should Lead to Billions in Economic Benefits for U.S.
Benefits from international regulations may double those of domestic policy.
A Worm with Five Faces
Max Planck scientists discover new roundworm species on Réunion.
Skyscraper Banner

Skyscraper Banner
Go to LabTube
Go to eposters
 
Access to the latest scientific news
Exclusive articles
Upload and share your posters on ePosters
Latest presentations and webinars
View a library of 1,800+ scientific and medical posters
2,900+ scientific and medical posters
A library of 2,500+ scientific videos on LabTube
4,200+ scientific videos
Close
Premium CrownJOIN TECHNOLOGY NETWORKS PREMIUM FOR FREE!