Engineering Yeast to Produce THC and CBD

In an article by Science Daily, scientists from UC Berkley report that biologists have successfully engineered brewer's yeast to produce THC and CBD. The study was conducted because it is much cheaper to extract cannabinoids from yeast compared to the buds of the marijuana plant. Biologist Jay Keasling says that "for the consumer, the benefits are high-quality, low-cost CBD and THC: you get exactly what you want from yeast". Furthermore, yeast makes it easier to study different chemicals that would otherwise be found in extremely small quantities is Cannabis sativa. 

Cannabinoids are not the first chemical to be engineered into yeast. Others include human growth hormone, insulin, morphine, and others. To turn yeast into chemical factories, scientists had to co-opt their metabolism. Instead of turning sugar into alcohol, yeast converts sugar into other chemicals that are then changed by adding enzymes. The scientists ended up injecting more than a dozen genes into yeast, some of which were copies from the marijuana plant. After adding genes and other enzymes, the yeast produced THC and CBD.

I think this alternative method of producing THC and CBD can prove to be helpful because it eliminates excessive costs and more importantly helps the environment. In states where marijuana is legal, pesticides and use of power account for a large amount of the use of energy in the state. Using yeast would help lower the environmental and monetary cost. It will be interesting to read about in the future because the topic of THC is already rather controversial. 

Controversy Over New "Gene-Editing Technique" NgAgo

Scientific discoveries in the biomedical world in the last 20 years have put us at the forefront of gene-editing, with many thanks to the CRISPR-Cas9 technique for significant advances and successes in research studies. Now, in China, a new gene-editing technique has supposedly been identified and has been claimed to be more precise and versatile than it's predecessor. NgAgo, an enzyme, was found to edit mammalian genes with precision and overwhelming success... in one study. The biologist to recognize the importance of NgAgo in gene-editing is Han Chunyu, refuses to step down from his claims that NgAgo has clear importance and accuracy in gene-editing.

Above: Han's study focused on editing the genes involved in eye formation of zebrafish embryos.

Due to the overwhelming success that Han's paper seemed to have, many scientists flocked to this new method to find out if it was really as perfect as Han had shown. Despite multiple attempts to recreate the exact conditions of the paper, no existing research has concluded that NgAgo is a gene-editor. From what has been seen thus far, it appears the NgAgo may bind to the gene in question and down-regulate the expression of just that gene. Unfortunately, this change in expression is not inheritable, thus possibly making NgAgo not a viable gene-editor.

There are hopes on the horizon for NgAgo however. A few scientists, Gaetan Burgio included, claim that the enzyme wasn't tested at the proper temperature (the temperature inside a bacterial cell). Further research will be needed to verify if NgAgo can be a superior alternative to CRISPR-Cas9, as this would change genetics for decades to come.