By Sam Jiang (ME ‘19)
For many, there’s still a mental block on munching on bugs, but more and more people are embracing insects as an environmentally-friendly source of protein. Ranching bugs is considerably less resource-intensive than raising traditional livestock, but there’s some nutrients we just can’t get out of insects—like vitamin A! This summer, Professors Medvedik and Janjusevic at the Kanbar Center are kicking off a new project as part Cooper Union’s STEM Program, with the ultimate goal of improving the nutritional value of edible insects.
Vitamin A deficiency is incredibly prevalent in poorer countries, and is especially dangerous—children without enough vitamin A are in danger of going blind. While rich in protein, crickets lack β-carotene, a precursor of vitamin A, and many other essential nutrients. Foods rich in β-carotene—such as carrots, or the genetically engineered Golden Rice—have a trademark yellow-orange color. The goal of the Golden Cricket Project is to use genetic engineering to create a cricket rich in both protein and β-carotene, which the body can synthesize into vitamin A.
Here’s the thing with genetic engineering, though: The more complex the organism, the harder it is to rewrite its genome without messing something up. Although we think of insects as fairly simple organisms, it’s still too difficult to genetically coerce the cricket into producing β-carotene on its own. Bacteria, on the other hand, grow rapidly, with some strains easily absorbing foreign genetic information, making them perfect candidates for β-carotene synthesis.
Before moving further, let’s have a small review session on high school biology. DNA codes for proteins, and proteins facilitate biological processes, like the production of vitamin A from β-carotene. In order to create a bacteria that produces β-carotene, the DNA sequence for every protein involved in β-carotene synthesis needs to be inserted into the bacterial genome. This bacteria will then be fed to the crickets; they will live and reproduce in the crickets’ gut, constantly churning out β-carotene, eventually turning the mundane cricket into a Golden Cricket.
Before the Golden Cricket can be made, many other issues need to be addressed. First and foremost is determining which bacteria to genetically transform into a vitamin factory. Professor Medvedic discusses potentially using common probiotics: “We’d like to use Lactobacillus, but maybe the type that we choose isn’t suitable for cricket gut.” Professor Janjusevic’s solution to that potential problem is to isolate and analyze an existing gut microbe, guaranteeing that the resultant β-carotene factory will be able to survive within the cricket. The final genetically-engineered microbe needs to be able to produce β-carotene and thrive and reproduce within the cricket in order to be considered a success.
Aside from technical difficulties, this project faces other, less scientific long-term hurdles. Most of Western society is still heavily opposed to eating insects, but the Golden Cricket itself is targeted more towards undeveloped nations where vitamin A deficiency is a real issue. In the media, there’s also a lot of misinformation and fear-mongering surrounding the use of genetically-modified organisms. Both of these are issues that can potentially limit long-term adoption of organisms like the Golden Cricket. ◊