This instructable will show you how to grow and culture your own glowing bacteria and use it to reinvent the light bulb!
I"ll show you how to grow your very own Vibrio phosphoreum or Vibrio fischeri from fresh sea fish (squid work well) and culture it onto special agar gel that you can make at home or simply buy ready-to-pour. The gel can be formed inside all kinds of things that you want to make glow a cool greenish/blue color !!!!
The glowing vibrio bacteria are marine life forms that live alone or in a symbiotic relationships with fish and squid inside their light organs or as parastites. Alone the bacteria don't really glow but in groups of large enough number something amazing happens called quorum sensing ..... The bacteria upon realizing they have enough of each other around turn on genes that allow them to GLOW !!!! The light that is emitted is super efficient around 98 % meaning that only 2 % is lost through heat, thus the light is cool and that's very COOL.
Here is some good info on v. fischeri
It's these amazing little guys (1/1,000,000 of a meter long) that will power our lightbulb !!!! If properly cultured your lightbulb will glow for about a month using zero electricity and zero pollution!!!! Granted its not incredibly bright but you can save electricity costs if you replaced a night light , or you could use it to read maps or books while camping and not worry about changing batteries in your flashlight and disposing of the batteries causing more pollution !!!!
Water Pollution Tester
This instructable will also demonstrate how glowing bacteria can test how toxic water is. The methods used are much more Eco friendly than chemicals and processing ..... So not only does bioluminescent bacteria reduce pollution , they can also DETECT IT !!!! The glowing process is a direct result of the bacteria's metabolism. Fresh clean water does not affect its cellular metabolism or how bright it glows. However even slight toxins that we can't smell , see or taste can alter the bacteria's metabolism and will reduce the amount of light they can produce. By comparing the amount of light emmited from bacteria treated with clean water to that of the sample at hand ..... Say from a stream near a power plant we can assess the level of toxicity in the water !!!!
Here is a video of what the bacteria look like ALIVE under high magnification:
Step 1: What you'll need
Step 2: Get your hands on some dead sea fish
If you live by the ocean, GREAT. Just go down to the local fish market and get some fresh ( never frozen) squid, shirmp or fish from the sea. I tend to think squid is the best, then shrimp then sea fish since vibrio fischeri etc live inside the light organ of the bobtail squid, but there are tons of these guys all over the ocean. With a little luck the seafood you pick up will have the strains on it, if not, just try again or buy online like the rest of the land locked people. If you are land locked but visiting the beach you may be able to put the fish in a jar, then pack the jar inside a cooler with ice untill you get home but its not a guarntee. Or you can take some sterile agar culture plates with you and grow some bacteria while your on vacation and take it back home to your lab....your family may think your a bit strange but it's worth it ( I did it on a recent trip to Cali muwahahaha).
Step 3: Make some bacteria food method # 1
Like you and me bacteria need food to grow so let's make some food that our bacteria will LOVE. Its full of vitamins, amino acids, carbon, minerals and of course salt, without salt they won't live (they live in the ocean after all).
TSA agar gel recipe:
Per Liter of deionized water: (you can always reduce it by 1/2 or 1/4 if you don't need the whole liter)
Mix together in a large beaker or saucepan on a heating plate or stove.
If you are going to use a pressure cooker you just have to heat it up until it mixes because using the pressure cooker to autoclave it will sterilize it...if you don't have a pressure cooker bring the mix to a steady controlled rolling boil to sterilize it.
Pressure cooker instructions (wannabe autoclave)
Your agar gel and petri dishes are now completely sterilized !!! ( the steam molecules created under pressure bounces around and kills any organisms that were present)
P.S. you may want to research how to use pressure cookers if you haven't used one before as they can be a little scary.
No pressure cooker instructions:
I HIGHLY recommend buying some sterile petri dishes from the net (around $7 U.S.) because it will ensure your bacteria don't get contaminated with other bacteria that are competing for the same space. But if not you can try boiling glass bowls or dishes that can withstand high temps....like pyrex for example for about 15 min.
Now that you have sterilized agar solution AND sterilized petri dishes or bowls and while both are just cool enough to handle (use a oven mit) pour the solution into the dishes and cover with lid or plastic wrap if using bowls.
Let cool until agar solution cools and hardens into a gel, when it hardens flip the dishes upside down...this ensures no bacteria fall on the gel from the lid.
They are now ready for your bacteria.
Step 4: Bacteria Food Method # 2
A second method if you want to make bacteria food is to make your own nurtient agar from scratch (funner and cheaper). We will use PANCREATIN to digest the casein in milk into nutrients the bacteria can use and add some salt for minerals and agar-agar flakes to thicken it into a gel.
Pancreatin can be found at your local vitamin store...it's used by people that have trouble digesting food due to problems with thier pancreas. The pancreas releases digestive enzymes. The pancreatin pills contain porcine (PIG!!!) amylase, lipase and protease that disolve protien, fat and carbs. OINK OINK.
You will need:
Step 5: Bacteria Food Method # 3
Step 6: Let the fish glow
Note: Depending on temperature of the room and other factors, a newly streaked colony will take about 18-48 hours to grow large enought to turn on their glowing genes (lux genes).
Step 7: Culture more bacteria
You'll notice that the bacteria like to grow in "colonies" or little circles...pick the brightest one and swab it or even "fish it out" with the loop, then transfer it to a fresh agar plate and streak it many times across the plate. Again let it grow in a cool dark place. Incubate for 18-24 hours.
Your plate should be aglow with bacteria. Muwhahahahha! BACTERIA!!!!
P.S. Interestingly a cousin to vibro fischeri and phosphoreum is vibrio cholerea which is the deadly cholera bug (well deadly if you don't have acess to basic medicine like IV fluids) so just in case, I would always wash your hands and wear gloves and goggles when messing with bacteria.
P.P.S You may notice that your bacteria seem to streak across the plate as they grow, this is becasue your glowing buddies have tails called flagella that spin like a propeller on a boat and can swarm around!!!
Step 8: Make your bulb
I made mine by taking the back off of a lightbulb and pouring the gel in such a way that I made a nice slant of agar medium to display the bacteria.
Step 9: Inoculate your bulb
Step 10: Water Pollution Tester
Just add a drop of distilled water to one half of a glowig agar plate and a drop the suspect water on the other half and observe the change in bioluminescence over a few days compared to the distilled water.
PS. This is a demonstration only.....although if the water I was testing made my bacteria go dim...I would for sure reconsider drinking it haha.
Step 11: How to care for and use your bacterial buddies
Some IMPORTANT things to remember if you want all your hard work to pay off and keep your bacteria glowing......
Make Frozen stocks:
I've been experimenting with making frozen batches that can be stored then used...I'm testing how long the samples stay viable.
To use samples take a needle and heat it up till its red hot...let cool then scrape the frozen sample then streak it on a fresh agar plate.
Still experimenting on how well this works.