A few years ago, "Glowing Plants" raised $484,000 on Kickstarter. Backlash followed and the platform banned gene-editing projects.
The original company died in 2017, but others took their place.
These are the highlights. 🧵
Our story begins in molecular biology's golden era, 1986.
A small cadre of biologists & chemists at UCSD reported, in @ScienceMagazine, the "stable expression of the firefly luciferase gene in...transgenic plants."
That same year, undergrads at the University of Cambridge continued the trend.
They put the firefly luciferase genes into bacteria & engineered the proteins to glow brighter; enough to read a book.
Was this an inflection point?
Were glow-in-the-dark plants ready for the home?
Antony Evans certainly thought so.
On 23 April 2013, he launched a project on Kickstarter. The goal: "Natural Lighting with no Electricity." The company, Glowing Plants, aimed to send Arabidopsis plants to those who pledged $40.
To make the plants glow, Glowing Plants would first have to insert SIX genes into Arabidopsis. Even then, there was no guarantee that the final plants would be bright.
"They never could get all six in at once," wrote @sarahzhang.
So, why this obsession with glow-in-the-dark plants?
The market, historically, is small. These will only make it into every house when the plants are so bright that people say, "Holy shit, that's a bright plant."
Until then, I'd wager that every company is destined to nichedom.
There are interesting applications for glowing plants in ag, though.
John Deere backed MIT-made plants, developed by @Inner_Plant, that glow when attacked by pests. Satellites detect problem plants, and alert farmers. The company raised a $16M Series A.
Last Sunday, @AsimovPress published an article explaining why it's so hard to diagnose tuberculosis.
Here are 10 interesting things we learned about TB while editing it:
1. TB (not malaria) is the deadliest infectious disease. It kills >1.2M people each year.
2. At its "peak" in the 19th century, TB killed 1-in-4 people in Europe and America.
It killed Chopin, Thoreau, Kafka, and Eleanor Roosevelt. The disease was dubbed "the white plague," as it made victims pale.
(Edvard Munch painted his sister, who died of TB at the age of 15.)
3. TB was also, oddly, romanticized by poets at the time.
“How pale I look!” wrote the poet, Lord Byron. “I should like, I think, to die of consumption … because then the women would all say, ‘see that poor Byron — how interesting he looks in dying!’”
2. A tool called TATSI enables precise DNA insertion in plants.
It works by fusing transposase proteins with CRISPR nucleases to deliver custom DNA to specific sites in the genome. So far, it's been tested in Arabidopsis and soybean plants.
In Shanghai, I visited BluePHA, a synthetic biology startup that uses engineered microbes to manufacture biodegradable plastics.
They make ~5,000 metric tons/year, have products available on the market, and are scaling to 50,0000 tons/year. 🧵
BluePHA makes PHAs, a type of polyester made by many organisms in nature. The company can mold these PHAs into lots of different plastic products, such as cups (right) or spools of thread (left) to make bags and clothes.
Many plastics sold on the market are touted as "biodegradable," but aren't actually biodegradable.
PLAs, a common culprit, only break down at high temperatures. They will not disappear if placed in the soil in your backyard.
PHAs are fully biodegradable at normal temperatures.
Cells are fast and crowded places. Numbers help us make sense of them.
Here are five of my favorite "bionumbers."
1. ATP synthase spins 134 times/second. That is much faster than the propeller on most piston airplanes, and about half the r.p.m. of a Boeing 737 jet engine.
2. An mRNA is (much) larger than the protein it codes for.
A single nucleotide of RNA is 3x heavier than an amino acid. Three nucleotides are required to encode each amino acid; not to mention the untranslated regions, polyA tail, and so on.
(Sources are in image descriptions.)
3. A cell is 70% water by mass.
Of the remaining 30%, proteins account for more than half (55%). DNA accounts for very little; about 3% of dry mass.
But, interestingly, there are many water-dwelling, photosynthetic microbes that express GAS VESICLES. These are protein compartments, filled with gas, that help the cells float up or down in water to capture sunlight.
A visual ode:
Heinrich Klebahn, a German microbiologist, was first to discover gas vesicles amongst some cyanobacteria that he collected from a lake.
Gas vesicles come in many shapes and sizes.
Sometimes they are short, and other times they are long.
Gas vesicles are made from between 8-14 genes. These genes can be engineered to change the properties of gas vesicles.