Monthly Archives: June 2017

Gene therapy and a range of biological research rely on the efficient delivery of nucleic acids into cells through the process known as transfection. Most widely-used transfection approaches for mammalian cells rely on electrostatic forces, usually taking advantage of cationic reagents to bind to negatively-charged nucleic acids and form strong ionic complexes. Cells then grab these complexes and internalize them through a process called endocytosis. However, the concentration of positive charge in the reagents can kill cells, and some cellssuch as embryonic cells, neurons, or cells directly isolated from tissuedont incorporate the nucleic acids successfully.

Now researchers report a novel transfection technique, SnapFect, that relies on bio-orthogonal moleculesa class of chemically-reactive molecules that dont interfere with biological systems (ACS Cent. Sci. 2017, DOI: 10.1021/acscentsci.7b00132). The team designed nanoparticle liposomes carrying a bio-orthogonal ligand. When they add those fatty particles to cell culture, they fuse into the cell membrane within seconds, leaving the ketone ligand exposed on the surface. The team then packages the nucleic acids to be delivered in complementary lipid complexes decorated with oxyamines. When the oxyamine particles are added to the cells, these functional groups react quickly with the cell surface ketones. The membrane-bound nucleic-acid complex is then pulled into the cell via endocytosis, and the nucleic acid can be expressed. Its not based on electrostatics but on click chemistry, says Muhammad N. Yousaf, a chemical biologist at York University. Thats why basically every cell is transfected with the nucleic acid.

Commercial transfection reagents already bring in about $1.5 billion per year. Yousafs team compared SnapFect to two widely-used kits: Lipofectamine (Life Technologies) and ViaFect (Promega). SnapFect transfected cells with a 68% overall efficiency while the other two transfected 19% and 29%, respectively.

Yousaf launched a company called OrganoLinX that this month began selling SnapFect ($350 for 20-25 transfections). We focused on making [the kit] just as easy to use as other commercial products out there, he says.

Besides improving efficiency, researchers could also pre-treat one batch of cells to decorate them with ketones and then mix them with other cell types before adding nucleic acids. Just the pre-treated ones will be transfected, Yousaf explains. Its like precision transfection. Because the team can create a variety of complexes using the oxyamine particles, the technique can also deliver other molecules such as proteins into cells.

I think its an interesting step forward, says James H. Eberwine, a molecular neurobiologist at the University of Pennsylvaniaparticularly the techniques universal applicability to DNA, RNA, and proteins, as well as the specificity conferred by the click chemistry approach.

Eberwine adds that while the study compares SnapFect to two widely-used techniques, researchers often optimize those techniques for their particular applications and achieve much higher efficiencies than those noted in this study. I would certainly try it, he says, and if it really does have the higher efficiency then I could see value in doing this.

Currently cell surface modification with ketones must occur shortly before addition of the oxyamine-bundled cargo. But SnapFect would be especially powerful if the ketone modification was more permanent, Eberwine says. That way, researchers could pre-engineer the surface of immature cells, then allow those cells to develop, migrate, and find their place in the local microenvironment of an experimental system before they get transfected. This would be a real boon, he says.

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Genetic engineering through click chemistry - The Biological SCENE

The 20th century veggie burger was a beige patty packed with whole grains and carrot chunks, sold in a brown paper wrapper. The 21st century version? Its bloody-pink and fleshy, thanks to heme, an ingredient created via genetic engineering.

To those steeped in the natural-food movement, the acronym GMO for genetically modified organisms has traditionally been almost as taboo as a plate of braised veal. However, that view could be changing as a new generation of Bay Area entrepreneurs upends the alternative meat and dairy industry, using biotechnology to create vegetarian foods that taste more like meat and promise ecological advantages to boot.

As somebody who has my entire life been a hard-core environmentalist I went vegan for a large part for that reason genetic engineering is one of the most important tools we can use in terms of environmental conservation, said Mike Selden, co-founder and CEO of Finless Foods in San Francisco, which is replicating fish fillets out of stem cells, though not currently with genetic engineering.

Not everyone agrees, and as these products hit the market including the aforementioned veggie burger that bleeds from Impossible Foods consumer and environmental groups have called for greater oversight and testing than whats currently required by the federal government.

The GLP aggregated and excerpted this blog/article to reflect the diversity of news, opinion, and analysis. Read full, original post:Meatless, tasty and genetically modified: a healthy debate

Original post:
21st century veggie burger: 'Bloody-pink and fleshy' thanks to genetic engineering - Genetic Literacy Project

Twenty years ago, proponents of genetic engineering promised that GMO foods would increase yields, reduce pesticides, produce nutritious foods and help feed the world. Today, those promises have fallen far short as the majority of GMO crops are engineered to withstand sprays of Roundup herbicide, which is increasingly documented as a risk to human health.

Now, new genetic engineering technologies such as synthetic biology and gene editing are being hailed with the same promises of revolutionizing food production, medicine, fuels, textiles and other areas.

But a closer look at this next generation or "GMOs 2.0" technologies reveals possibly even greater risks than existing GMO technology with possible human health risks and negative impacts on farming communities worldwide, among other unintended consequences. And while products developed using current genetic engineering methods are regulated by the U.S. government, GMOs 2.0 products are entering the market with few or no regulations.

Synthetic Biology: Extreme Genetic Engineering

While traditional genetic engineering involves inserting genes from one species into another, GMOs 2.0 technologies like synthetic biology aim to create life from scratch with computer-synthesized DNA.

"Genetic engineering has moved on from the first generation GMO crops," said Jim Thomas, program director at the ETC Group, a non-profit advocacy group that tracks the new GMO technologies. "There are different ways to genetically engineer an organism by creating synthetic DNA or editing DNA."

The ETC Group describes synthetic biology or "extreme genetic engineering" as "the design and construction of new biological parts, devices and systems that do not exist in the natural world and also the redesigning of existing biological systems to perform specific tasks."

"Synthetic biology is about synthesizing genetic sequences, designing them increasingly from scratch as if they were parts to put together in a particular way to get a predicted outcome," Thomas said.

The synthetic biology process involves altering the DNA of microorganisms such as algae, bacteria and yeast so they produce compounds like flavors and fragrances that previously have been extracted from plants. Scientists and software engineers are altering the DNA of existing microorganisms and designing new ones.

Synthetic biology companies are producing a wide range of compounds for food, pharmaceutical, fuel and industrial use. Evolva has created a synthetic biology form of vanillin, an alternative to natural vanilla extract. Perfect Day has engineered yeast cells to produce proteins similar to those found in cow's milk with the aim of producing vegan milk. Impossible Foods engineered heme, a molecule that makes meat sizzle and look pink for the company's meatless Impossible Burger. According to the ETC Group, there are some 350 synthetic biology products on the market or in development.

The claimed benefits of synthetic biology products such as flavors and fragrances are that they can be produced in greater and more consistent quantities and at lower prices than crop-based plant materials that are subject to climate conditions, crop failures and transportation logistics.

CRISPR Gene Editing

Another GMOs 2.0 technology is a gene editing method called CRISPR. This enables scientists to edit parts of the genome by removing, adding or altering sections of the DNA. The aim is to activate or deactivate genes to produce a desired effect. Proponents say CRISPR has the potential to treat illnesses that have a genetic basis such as cancer, sickle cell anemia, hepatitis B or high cholesterol.

GMO seed companies are using CRISPR to develop new plant varieties. Cibus used the technique to develop an herbicide tolerant canola. Pioneer Hi-Bred is developing waxy corn hybrids with high starch content for food and non-food uses. Monsanto recently announced it was licensing the CRISPR technology to develop new seed varieties.

Proponents say CRISPR is "the simplest, most versatile and precise method of genetic manipulation."

"It's a lot more precise in that it targets a specific gene in the genome where it exists while genetic engineering involves inserting a gene at random in the genome, which could disrupt the functioning of other genes," said Jim Orf, professor emeritus, plant breeding and genetics at the University of Minnesota.

But Thomas said scientists are seeing unintended effects using CRISPR. In fact he said "some scientists are intentionally not using CRISPR because of off-target effects." Orf also admitted that the technology is not "100 percent foolproof." Dr. J. Keith Joung of Massachusetts General Hospital said there is growing evidence that CRISPR might alter regions of the genome other than the intended ones.

Technology Risks

Causing unintended consequences is one of the problems with current genetic engineering methods, and these could be even worse with GMOs 2.0 technologies, particularly synthetic biology.

"You're not just adding one gene with all the implications of that. Here you are dealing with stretches of DNA that are invented on a computer. The level of novelty and the depth of intervention are much more significant."

Synthetic biology techniques could create secondary metabolites or molecules or different levels of compounds that could have negative impacts.

An underlying problem with the techniques is that they are based on an outdated premise of how biology and nature function.

"One of the dangers with synthetic biology is that it pretends that life is a linear, predictable system that you can engineer as if you can re-engineer a car or computer and that DNA is just a code," Thomas said, "But all those metaphors are falling apart in the biological sciences."

There are also social concerns. Companies like Evolva that make synthetic biology flavors like vanillin are hurting the market for natural vanilla produced by farming communities in Madagascar.

"These companies are trying to disrupt those markets and take that value," Thomas said. "If you can produce vanillin, then you will start affecting the supply chains and livelihoods of vanilla farmers."

Natural and Non-GMO Claims

Another problem is that some synthetic biology and gene editing companies are claiming that their products are natural or even non-GMO. Cibus calls its gene-edited canola "non-transgenic." Synthetic biology companies say that even though the production organism they create is a GMO, they claim the final ingredient is non-GMO.

"They'll argue that the (GMO) production organism is a just a processing aid," Thomas said. "That's a bit like saying a cow is a processing aid for making milk."

The Non-GMO Project also disagrees.

"There is a growing attempt on the part of biotechnology companies to claim that new types of genetic engineering, such as gene editing and synthetic biology, are not actually genetic engineering," said Megan Westgate, executive director of The Non-GMO Project. "To bring clarity in the face of this misleading trend, the Non-GMO Project has explicitly included these technologies in our Standard and cannot be used in a Non-GMO Project Verified product."

On the organic side, the National Organic Standards Board has proposed redefining genetic engineering in the National Organic Program to include GMOs 2.0 technologies, but the new definition hasn't yet been formally adopted.

No Regulation

There is virtually no regulation of GMOs 2.0 techniques in the U.S. The U.S. Department of Agriculture doesn't consider gene-edited crops such as Cibus's canola and Pioneer's waxy corn as falling under the agency's regulations for genetically engineered crops.

But Orf said the U.S. Department of Agriculture is deciding how GMOs 2.0 crops should be regulated. "They're reviewing their process to see if these crops should be regulated on a case-by-case basis or in a general way. These are different technologies doing things in a different way than transgenics."

Synthetic biology manufacturers are claiming their products such as vanillin are the same as the natural compounds and consider them to be "generally recognized as safe" or GRAS.

"Some companies are going to the Food and Drug Administration and saying 'we would like this to be GRAS' and the FDA is doing that," Thomas said.

Can GMOs 2.0 products be tested to detect their presence as current GMOs are?

"At this point, they are not developed, but they are developable," Thomas said.

"The companies will say their products can't be tested because they are the same as natural compounds. But if you talk with testing labs, they say they could develop a test. It is inevitable that tests will be developed because you have certifiers like the Non-GMO Project saying you can't use synthetic biology products."

See the rest here:
Next Generation of GMOs Escapes Regulation - EcoWatch