Tag: Biosensors

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Delving into SciComm by Tyler’s Instagram stories: Biosensors, Komodo dragons, lab meat, and more!

Stories from the SciComm by Tyler Instagram account

I often come across interesting biology facts. I spam these facts in polite conversation, but I’ve also decided to share them in a more productive way on Instagram. On the SciComm By Tyler instagram account, I’ll post detailed drawings coupled to nuggets of biological intrigue. Some of these will come from blog posts. Through the stories feature, I’ll share more bite-sized biological morsels. I’ll couple the stories with goofy doodles (sometimes I’ll recycle these from my gallery :P). At the end of each week, I plan on delving into the stories in a little more detail through a blog post.

Below, I expand on my first week of stories. Enjoy!

Please follow me on Instagram if you like what you see :D.

Biosensors are biological machines that detect objects and events

Doodle of a DNA biosensor

I wrote a bit about biosensors in an older blog post. As a refresher, biosensors are biological machines that detect specific objects and events. They have many research uses. They can detect chemicals, they can detect organisms, and some can even count how many times cells divide.

I first became enamored with biosensors during my PhD work. For part of my work, I tried to get bacteria to turn sugar into gasoline. To see if my bacteria were accomplishing this goal, I designed a biosensor. This biosensor made the bacteria turn red if they produced gasoline-like chemicals. Indeed, the more gasoline-like chemicals they produced, the more red they’d become. Unfortunately, my biosensor wasn’t particularly sensitive so I abandoned it (such is the nature of many experimental research projects!).

Others have created more useful sensors. The doodle above illustrates a biosensor that detects DNA. Such biosensors bind to specific DNA sequences and glow. They help scientists understand how DNA sequences interact with other things in cells. Using many different biosensors, scientists learn how cells function. Scientists can then use their knowledge to create therapeutics or even design cells that do cool things like attack cancer cells!

Komodo dragons use venom to kill prey

Doodle of a Komodo dragon

I think Komodo dragons are super cool. Even if they don’t breathe fire, they’re still basically dragons. Long ago, I was told that Komodo dragons don’t directly kill their prey. Supposedly, they instead transferred bacteria to their pray through biting. The resulting infections then killed their prey over time. Recently, I learned that RESEARCHERS DO NOT BELIEVE THIS ANYMORE. Indeed, when I was at the San Francisco Zoo a few days ago, I read that Komodo dragon bites inject venom into their prey. This venom kills prey through a mixture of physiological effects. For instance, the venom can lower blood pressure and prevent clotting. It’s not fire, but it’s pretty brutal!

Some frogs survive being frozen

Doodle of a frozen frog

Okay, I’m a molecular and cell biologist at heart, but I love me a good animal fact! I picked this one up while watching one of the many BBC nature documentaries on Netflix. I don’t have much more information than what’s in the image. I just think it’s really cool! Hopefully, I’ll dive into this in a dedicated post at some point.

Some bacteria inject DNA into plants

Doodle of an agrobacterium injecting DNA into a plant

Bacteria do soooooo much more than make us sick. There are many bacteria that do good things. We’ve even figured out how to turn some dangerous bacteria into useful tools. For example, there are bacteria that use teeny tiny needles to inject their DNA into plant cells. These bacteria naturally cause plant diseases. However, scientists have figured out how to use these bacteria to deliver useful DNA sequences to plants. They can even use these bacteria to make crops resistant to pests! Learn a little more about plant biotech in this post.

Complex meats are hard to make in the lab!

Doodle of lab grown meat

Many companies are working to grow meat and meat-like products in the lab. They hope to produce these “meats” more sustainably than livestock. They are having a lot of success growing meats like chicken nuggets or ground beef. However, it will be some time before we have more complicated meats like steaks or pork chops. The complex structures of these meats are difficult to create in the lab.

That’s all for this week. Please follow me on Instagram to check out my stories in real time. Cheers!

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Learning the Game of Life with Biosensors

Cartoon of a DNA Biosensor

There are many ways to learn a new game. You might read the instructions. You might look at diagrams of the game board. You might watch other people playing. You might even play the game yourself.

Similarly, when trying to understand how a cell works, researchers do all of these things. They read the cell’s DNA to learn what it encodes, they use special microscopes to get high definition pictures of cellular components, they watch the cell grow, and sometimes they even try to build new cells.

For all of these techniques to work, we must be able to observe key components of the games or cells under study. For example, if you were trying to learn how to play soccer and couldn’t see what was going on, you’d have a hard time learning the game. To study how a protein works, a researcher must be able to observe the protein in cells. The same is true for chemicals, DNA, and many other molecules a researcher might like to study inside a cell – you must be able to observe, measure and identify these things in order to learn what they do.

What is a biosensor?

Drawing of a protein-protein interaction biosensorA biosensor is one type of tool a researcher can use to observe molecules in cells. Biosensors are devices made of biological components like DNA or proteins (hence bio) and they detect or “sense” when different types of molecules are nearby (hence sensor). Biosensors report that they have detected something through an easily observable signal. You can think of biosensors like friends explaining a game to you for the first time, and showing you clearly what is going on. If the game was soccer, they could point to the goalie and say “That’s the goalie” and also scream “GOOOAAALLLLLL!!!” when a goal has been scored.

Biosensors work in many different ways but they often give researchers visual cues to show that they have detected specific molecules. For instance, some biosensors will start to glow red if there is a particular chemical in a cell. Other glowing biosensors will attach to specific sequences of DNA to show where those pieces of DNA are. Still other biosensors will make cells turn blue only if two proteins interact with each other.

What are biosensors used for?

Cartoon of a biosensor for glutamate

One interesting biosensor that I learned about recently is called iGluSnFr. This cleverly named biosensor glows bright green when it detects a chemical called glutamate. This ability is useful because glutamate is transferred between some cells of the brain when they communicate. You can therefore use iGluSnFr to determine if cells in the brain are talking to each other and even measure brain responses to things like visual cues. In this particular case, detecting glutamate serves as a proxy to tell researchers “Hey! These cells are talking to each other!”

Of course this is just the tip of the iceberg for biosensors. Researchers have produced biosensors to measure levels of toxic waste, to measure the acidity of cells, and even to detect Zika virus. Everyday, scientists are using biosensors to learn the rules of life and, as they get more precise, you may see these cool tools used to diagnose and treat disease!